Method for controlling the work function of at least one surface, electrodes, electrochemical cells, energy storage devices, photovoltaic cells, and electrical components thereof

Abstract

The present disclosure relates, inter alia, to a method for controlling the work function of at least one surface, comprising: measuring a first work function of a first surface; depositing a chiral system on the first surface to cause a change in the first work function; applying a potential difference between the first surface and a second surface to cause a charge transfer between the first surface and the second surface; and measuring a second work function of the first surface bearing the chiral system, the second work function being lower than the first work function. The interaction of the chiral system with the first surface is configured to cause charge rearrangement, spin polarization of the surface, and spin polarization of electrons injected from or into the first surface, thereby modifying the work function of the first surface. The present disclosure also relates to electrodes, electrochemical cells, energy storage devices, photovoltaic cells, and electrical components thereof.

Description

[Technical Field]

[0001] The present disclosure relates generally to electrodes, electrochemical cells, energy storage devices, photovoltaic cells, and electrical components. The present disclosure also relates particularly, but not exclusively, to methods for controlling the work function of at least one surface. [Background technology]

[0002] The following documents are considered relevant as background to the subject matter disclosed in the present invention.

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[0004] Acknowledgment of the above references herein should not be inferred as meaning that they are in any way relevant to the patentability of the subject matter disclosed in the present invention.

[0005] background The work function of any surface, whether solid or liquid, is defined as the minimum amount of energy required to move one electron from the interior of the material to infinity. The measured work function of a particular material will vary in the presence of contaminants or coatings. Various methods exist for measuring the work function of a surface, such as photoelectron spectroscopy, in which electrons are injected from the material with a defined photon energy and the energy of the electrons is determined. Another method is the Kevin probe technique. The Kevin probe is a non-contact, non-destructive measurement device. It is based on vibrating a capacitor and measuring the surface potential difference between the surface under study and a vibrating reference surface.

[0006] Numerous charge storage devices (e.g., thin-film batteries) and electronic devices (e.g., organic thin-film optoelectronic devices, including organic light-emitting diodes (OLEDs), organic thin-film transistors (TFTs), or organic solar cells (OSCs)) require at least one electrode material that exhibits a work function low enough to allow either electron injection into or electron extraction from the lowest unoccupied molecular orbital (LUMO).

[0007] Regarding materials with low work functions, various metals, such as Li, Na, Mg, Ca, or Zn, are suitable candidates for such electrodes. However, low-work-function electrode layers are usually applied using thermal evaporation or sputtering, which is costly and complicated and not easily applicable to many metals, such as Zn. In addition, due to the high reactivity of pure metals with air and water, these electrodes must be handled in a high vacuum, requiring sophisticated equipment.

[0008] Various strategies have been proposed to solve at least some of these problems. For example, Zhou et al., Science 2012, 336(2) 327-336, disclose that surface modification with polyethyleneimine can lower the work function of conductors, thereby enabling the use of alternative electrode materials that are less susceptible to oxidation. However, this method requires additional manufacturing steps, and it remains difficult to achieve a low work function comparable to that of, for example, pure alkali metals. U.S. Patent Application Publication No. 2005 / 0019976 takes a different approach, disclosing electrodeposition and printing techniques that do not require a vacuum environment. International Publication No. 2008 / 127111 also proposes a method for producing electrodes by electrodeposition, in which a plating solution containing an ionic liquid and metal or metalloid ions is applied, and the ions are reduced and deposited to form an electrode on the surface of an electroactive material. However, these methods require a drying step and careful processing of the formed electrodes under an inert gas atmosphere to avoid contact with air and water. Furthermore, the device configurations that can be obtained by these methods are limited in terms of electrode placement, because due to the reactivity of the electrode material with residual solvents (e.g., water), depositing a solution-processed layer on top of the electrode material (or alternatively, depositing an electrode on top of a solution-processed layer) is either not possible or results in a non-uniform, poor quality electrode layer. WO 2013 / 019993 relates to a method for enhancing charge injection by providing an equipotential source layer containing non-reducing mobile ions.

[0009] Lithium-ion batteries (LIBs) are the most common type of electrochemical energy storage, used in various industries, including electric vehicles, telephones, portable electronic devices, and stationary grid power stations [1, 2]. They are known for their high energy density, reliability, and efficiency [3-6]. Nickel-rich layered lithium transition metal oxides are promising cathode materials for next-generation LIBs used in automotive applications due to their high specific capacity (200-250 mAh / g), high operating voltage (approximately 3.6-3.8 V), good rate capability, and relatively low cost [7-9]. The active material LiNi 0.8 Mn 0.1 Co 0.1 The chiral organic coating on O2 (NMC811) improves the discharge capacity and rate capability and reduces the retention of the material.

[0010] However, these materials can suffer from structural and interfacial instability during repeated charge-discharge cycles, leading to performance degradation and safety concerns. One challenge is that highly reactive materials can promote electrolyte decomposition, resulting in rapid capacity loss and overall poor battery performance [7, 10]. Internal resistance and overpotential also play important roles in battery performance. Low electronic resistance leads to higher power density and reduced risk of overheating, while low overpotential results in higher energy density

[11] .

[0011] At high cutoff voltages (>4.4 V vs. Li+ / Li), the high Ni content in the NMC811 cathode material severely impacts capacity fading and relatively poor rate performance.

[12] The major causes of capacity fading can be attributed to structural degradation induced by (i) the accumulation of NiO phases on the surface, (ii) lithium residues on the surface that can easily absorb H2O and CO2 to form Li2CO3 and LiOH, which lead to high pH and high interfacial resistance in the cathode material, and (iii) the formation of parasitic by-product HF in the electrolyte, which dissolves transition metal ions on the NMC material, the most important factor in continuous electrochemical reactions during charge and discharge. [13, 14] Unwanted transition metal dissolution from the cathode can destroy the structural stability of the cathode active material and change the composition of the solid electrolyte interphase (SEI).

[15]

[0012] Therefore, it is not surprising that numerous efforts aimed at reducing degradation and improving battery performance have been reported in the literature. A promising approach involves surface modification of cathode materials through coating processes [16, 17]. This approach aims to address the capacity fading of Ni-rich cathode materials during extended charge-discharge cycling. Protective surface modifications include surface coatings of both the cathode and anode using a core-shell structural design via wet chemical methods

[18] , physical vapor deposition

[19] , chemical vapor deposition

[20] , and atomic layer deposition [21, 22]. Surface treatments can protect the contact between NCM cathode materials and the electrolyte, thereby inhibiting transition metal dissolution from the cathode and reducing side reactions, thereby improving electrochemical performance in terms of rate capability, specific capacity retention, and long-term cycling [23, 24]. Furthermore, coatings can reduce the microcracking and oxygen release associated with these changes after extended charge-discharge cycling, which can lead to safety hazards.

[0013] This approach has been extensively investigated in lithium-ion batteries where the cathode materials were protected with stable transition metals, metal oxides such as Al2O3, SiO2, TiO2, ZnO, and ZrO2, phosphates (AlPO4, Li3PO4), and fluorides (AlF3) [25, 26], polymer materials

[27] , and metal-organic frameworks (MOFs) [28, 29] for their resistance ability to avoid direct electrode-electrolyte contact and HF corrosion on the cathode materials during extended charge-discharge cycling. However, most of these inorganic coating materials are not electrically conductive, form parasitic by-products with lithium and the cathode material, and exhibit opposing effects on electrochemical performance. In addition, most of these coating materials are not suitable for Li + It is an ionic insulator and the Li + It inhibits the diffusion of ions and does not fully utilize the capacity of the cathode material.

[0014] The controlled oxygen reduction reaction (ORR) is central to the development of aerobic life

[29] and clean energy technologies such as fuel cells [31,32]. This process starts with triplet ground-state oxygen and terminates with all singlet-state products. Thus, spin constraints in oxygen reduction can be overcome. Typically, this has been achieved by using electrodes with large spin-orbit coupling (SOC).

[0015] The ground state of diatomic oxygen is a triplet electronic state Understanding the detailed mechanism of ORR is challenging because the reaction products are closed-shell singlet states, whereas spin selection rules must be considered. Indeed, current fuel cell technology utilizes rare metal catalysts with large spin-orbit coupling. In contrast, aerobic organisms perform ORR without the need for precious metals. While some enzymes possess metal cofactors with large spin-orbit couplings that can relax spin constraints during the reaction

[33] , enzymes without metal cofactors are known to promote efficient oxygen reduction [34,35]. Clearly, important details of the biochemical mechanism remain unknown.

[0016] The intrinsic activity of ORR catalysts has not been significantly improved, and efforts to develop catalysts with reduced overpotentials have met with limited success.

[36] The best ORR catalysts are platinum-based, and oxygen adsorption onto them is highly efficient at low reduction potentials, resulting in inefficient proton and electron transfer. Only at high reduction potentials can the stability of the adsorbed oxygen decrease and the reaction proceed.[37,38] This has been considered the cause of the observed ORR overpotentials and a key bottleneck in catalyst development. Summary of the Invention

[0017] There is a need to provide methods for preparing surfaces with low work functions. In particular, there is a need to provide inexpensive and convenient methods for producing low work function electrodes that can be used in the fabrication of a wide variety of device configurations, thereby providing, among other things, electronic devices and / or charge storage devices with improved charging times.

[0018] The presently disclosed subject matter relates to a novel technique for controlling the work function of a surface through the deposition of chiral systems. Chirality is the property of an object that makes it non-superimposable, much like left-handed and right-handed hands. Chiral molecules are essential in chemistry and biology because they can have different properties and reactivities compared to their mirror images [44, 45]. Hereinafter, the term "chiral system" refers to molecules with non-superimposable mirror images (i.e., enantiomers). A chiral system may be chiral at the molecular level (intrinsically chiral) or chiral due to the structure formed by multiple molecules (each molecule is not inherently chiral). In some embodiments, it may contain homochiral or one-directionally chiral molecules, in which all chiral molecules in a given sample have the same chirality or handedness (e.g., either left-handed or right-handed, but not a mixture of both). A surface or a portion of a surface is made of or coated with a chiral material. Chemically binding chiral systems to a surface or physically adsorbing a film of chiral material (molecular or inorganic) onto a surface has been found to change the work function of the surface. This allows electrons to leave or enter the surface at a lower potential than would be the case for an uncoated electrode or an electrode coated with an achiral film. Therefore, chiral coating of a surface can be used to lower its work function. As mentioned above, adsorption of molecules onto a surface changes its work function by changing the dipole moment perpendicular to the surface. In addition to a simple change in the dipole moment, the presence of chiral molecules induces spin polarization in a magnetized substrate, which, as described in

[39] , makes the transfer of electrons with one spin more favorable and reduces the resistance at the substrate-molecule interface.

[39] described Kelvin probe measurements on a ferromagnetic thin-film electrode coated with a self-assembled monolayer of chiral molecules and revealed that the penetration of electrons from the metal electrode into the chiral molecules depends on the magnetization direction of the ferromagnet and the chirality of the molecules.The work function change in magnetic electrodes described in

[39] is due to a change in the electrode's magnet orientation. However, using magnetic or ferromagnetic electrodes in electrochemical systems is impractical, costly, and very restrictive in terms of fabrication of various device configurations. Furthermore, despite the change in the work function of the magnetic electrode, the use of magnetic or ferromagnetically coated electrodes does not allow electrons to enter or exit the magnetic or ferromagnetically coated electrodes at lower potentials and / or resistances than uncoated magnetic electrodes.

[0019] Our unique approach involves molecular chiral coatings, which are known to enable pure spin currents as a result of the chiral-induced spin selectivity (CISS) effect [40-43]. The CISS effect is a phenomenon in which the spin state of electrons passing through chiral molecules is selectively influenced by the handedness of the molecule [40,42,46,47]. In other words, the spin of electrons passing through left-handed molecules differs from that of electrons passing through right-handed molecules [30,32]. Therefore, charge transfer and transmission through chiral molecules generates spin-polarized electron distributions [48,49]. Spin-polarized electrons cannot backscatter in the chiral potential, resulting in reduced resistance

[50] . Electron spin is also important in chemical reactions in which most bonds are in the singlet state [51,52]. However, oxygen molecules are unusual in that they possess a triplet state in their ground energy level

[51] . Therefore, standard oxidation processes are spin-forbidden and have large overpotentials. In such cases, as discussed in more detail below for the oxygen reduction reaction, the CISS effect can be used to align multiple electron spins, thereby increasing the efficiency of these processes.

[53] Similarly, spin alignment can be used to increase the use of spin-polarized currents in electrolyzers and fuel cells, improving their efficiency. Indeed, the inventors have demonstrated that the use of chiral molecules as mediators for water splitting can improve efficiency by reducing the overpotential by 50%. [53, 54] In this study, we compared the electrochemical properties of chiral L-α-helical polyalanine (AHPA), [H]-C(AAAAAK)7-[OH], achiral 12-mercaptododecanoic acid (MDA), and untreated cathode material, all purchased from Sigma-Aldrich, Ltd., Israel. The chiral molecules coat the active material, and the chiral coating was shown to increase the specific capacity at both slow and fast charge / discharge rates. Specifically, the AHPA chiral-coated NCM811 cathode material improved efficiency by 6% and reduced the overpotential in the reduction process by 0.1 V, reducing energy loss and heating obstacles.

[0020] This disclosure presents techniques for reducing internal resistance and surface work function and improving electron transfer efficiency. This can be done by providing electrodes and coatings for electrodes made from or coated with chiral materials. The presence of chiral molecules induces polarization of electron spins, resulting in more efficient transfer of electrons with one spin and less resistance at the interface. The inventors of this disclosure provide novel electrodes and coatings for electrodes and electrode components that exhibit improved electron transfer efficiency.

[0021] This technique can be used to improve the operation of batteries, electrolyzers, fuel cells, switches, connectors, electrochemical capacitors, photovoltaic (PV) cells, and any other device where the Schottky barrier should be controlled. Chiral molecules and chiral organic and inorganic films can be used to control the electrode-electrolyte interface of an electrochemical system, thereby tailoring the surface work function and / or spin state at the electrode-electrolyte interface to optimize the operation of the electrochemical system.

[0022] According to another aspect of the present disclosure, a method for controlling the work function of at least one surface is provided, comprising: measuring a first work function of a first surface; depositing a chiral system on the first surface to induce a change in the specific first work function; applying a potential difference between the first surface and a second surface to induce charge transfer between the first surface and the second surface; and measuring a second work function of the first surface bearing the chiral system, the second work function being lower than the first work function. The interaction between the chiral system and the first surface is configured to induce spatial rearrangement of charges on the first surface, spin polarization of the first surface, and spin polarization of electrons injected from or into the first surface, thereby modifying the work function of the first surface, allowing electrons to enter or exit the first surface at a lower potential energy, and / or reducing the electrical resistance of the first surface to be lower than the electrical resistance of the first surface prior to the deposition of the chiral system.

[0023] In some embodiments, depositing the chiral system on the first surface comprises chemically binding the chiral system to the first surface or physically adsorbing the chiral system to the first surface.

[0024] In some embodiments, when a first surface at least partially supporting the chiral system is configured and operable as a working electrode and a second surface is configured and operable as a counter electrode, the method further includes, prior to applying the potential difference, interacting at least one chiral coated surface used as an electrode and another surface as a counter electrode with an electrolyte, the interaction between the chiral electrode and the electrolyte being configured to change the spin state at the electrode-electrolyte interface.

[0025] In some embodiments, the method further comprises immersing at least one of the electrode and the counter electrode in an electrolyte before applying the potential difference, wherein an interaction between the chiral electrode and the electrolyte is configured to change the spin state at the electrode-electrolyte interface.

[0026] According to another broad aspect of the present disclosure, there is provided an electrode for use in an electrochemical process. The electrode comprises a substrate having a conductive surface carrying a chiral system, the chiral system configured to control the work function of the electrode. Interaction of the chiral system with the electrode is configured to cause charge rearrangement, spin polarization of the conductive surface, and spin polarization of electrons injected from or into the conductive surface, thereby lowering the work function of the electrode, the potential energy required to initiate the electrochemical process, and the internal electrical resistance of the electrode.

[0027] The chiral system may comprise at least one organic and / or inorganic material with chiral properties, or any combination thereof. The chiral system may comprise a chiral polymer and / or a chiral inorganic film. The chiral system may be configured as a monolayer or multilayer structure that acts as a layer to improve charge separation. It may also comprise a self-assembled monolayer of chiral molecules or chiral biomolecules. The chiral system may be chemically bound to the substrate surface or physically adsorbed onto the substrate surface. The substrate may be made of at least one of a metallic chiral conductor and a semiconductor.

[0028] In some embodiments, the chiral system comprises at least one of the following chiral organic materials: polypeptides, oligopeptides, amino acids, proteins, DNA, helicenes, chiral polymers, small chiral molecules, or any combination thereof, or the following chiral inorganic materials: chiral oxides, chiral metals, and chiral crystals, or any combination thereof. The term "small chiral molecule" refers to a molecule that is less than 10 nm in thickness.

[0029] In some embodiments, the chiral system comprises chiral metal or semiconductor nanoparticles, for example, at least one of gold, silver, palladium, platinum, CdS, or perovskite nanoparticles, or any combination thereof.

[0030] In some embodiments, the electrode is configured as a light absorber. Additionally or alternatively, the substrate may be configured as a light absorber.

[0031] In some embodiments, the electrode comprises at least one layer of a light absorber supported on a substrate. The chiral system may comprise at least one layer of a light absorber having chiral properties.

[0032] In some embodiments, the electrode comprises light-absorbing nanoparticles bound to the substrate via a chiral system.

[0033] According to another broad aspect of the present disclosure, there is provided an electrochemical cell system including an electrochemical cell configured to at least one of electrolyze at least a first electrolyte or convert chemical energy of a fuel into electricity, and an electrode as defined above, wherein the electrode is configured to support a chiral system and to interact with the first electrolyte of the electrochemical system. The interaction between the chiral electrode and the first electrolyte is configured to change the spin state at the electrode-electrolyte interface, thereby optimizing the operation of the electrochemical system. Optimizing the operation of the electrochemical system can be achieved, for example, by reducing the impedance of the cell and improving the number of charge cycles.

[0034] In some embodiments, the electrochemical cell further comprises a counter electrode connectable to the chiral electrode and configured to interact with a second electrolyte in chemical communication with the first electrolyte, and potential energy can be applied between the chiral electrode and the counter electrode. The counter electrode can comprise a substrate having a conductive surface that at least partially supports the chiral system. The substrate can be made of at least one of a metal, a chiral conductor, and a semiconductor. The first and second electrolytes can be made of the same material or different materials.

[0035] In some embodiments, the electrochemical cell further comprises a membrane configured to separate the first electrolyte and the second electrolyte.

[0036] In some embodiments, the diaphragm comprises a substrate having a conductive surface that at least partially supports the chiral system defined above. The substrate may be made of at least one of a metal, a chiral conductor, and a semiconductor.

[0037] There is a need in the art for novel approaches to the oxygen reduction reaction (ORR) that can reduce the overpotential of the reduction reaction. Overpotential is an electrochemical term that refers to the potential difference between the thermodynamically determined reduction potential of a half-reaction and the potential at which the reaction is experimentally observed, and thus represents the voltage efficiency of the cell. Overpotential is a common problem in oxygen reduction systems because they typically require a relatively high onset potential compared to the working potential, i.e., the equilibrium potential of the net redox reaction.

[0038] The present disclosure provides electrodes and electrode coatings for use in oxygen reduction systems (e.g., fuel cell systems). Such electrodes are characterized by improved efficiency of electron transfer to oxygen (oxygen reduction reaction) and improved operation even for electrodes with high SOC. The electrodes of the present disclosure are made from chiral conductors or conductors coated with chiral materials / structures. The inventors have demonstrated lower overpotentials and higher current densities with chiral catalysts than with achiral catalysts. This effect arises from the spin selectivity that chiral assemblies impart to electron flow, i.e., the chiral-induced spin selectivity effect.

[0039] We hypothesize that the multielectron reduction (ORR) of dioxygen can be enhanced by the use of spin-polarized electrons, and that ORR efficiency can be improved by using chiral biomolecules

[55] , which are known to spin-polarize electrons via the chiral-induced spin selectivity (CISS) effect. Previous studies have demonstrated that electron transport through proteins

[56] , including proteins involved in respiration

[57] , is spin-dependent.

[0040] We investigated electrochemical ORR at electrodes modified with chiral organic monolayers and examined the effect of chirality on thin metal films and on platinum and gold nanoparticles. In each case, we compared the ORR performance, particularly the onset potential and current density, of the chiral modified electrodes with that of achiral analogs. Platinum nanoparticles were specifically chosen because they are the preferred catalyst in fuel cells.

[58] In some embodiments, the electrochemical cell system is configured to be immersed in an oxygen-containing solution and is operable to promote electron transfer from the electrode to oxygen and reduce the overpotential of the oxygen reduction reaction.

[0041] The rapid increase in energy demand and the rapidly growing interest in green energy have dramatically increased the need for energy storage devices. Lithium-ion batteries (LIBs) are the most common type of electrochemical energy storage used in various industries, including electric vehicles, phones, portable electronic devices, and stationary grid power plants. Among these, nickel-rich layered lithium transition metal oxides (LiNi 1-x-y Co x Mn y O2) is one of the promising cathode materials for next-generation lithium-ion batteries due to its specific capacity and high operating voltage. However, these materials suffer from structural / interface instability, resulting in safety concerns, among other issues. In this study, we demonstrate that a thin-layer coating of polyalanine chiral molecules can protect and improve the performance of Ni-rich cathodes. Specifically, NMC811 electrodes coated with chiral molecules exhibit lower voltage hysteresis and better rate performance. We attribute these results to the chiral-induced spin selectivity (CISS) effect, which aligns electron spins, thereby reducing the resistance at the electrode interface and dramatically lowering the overpotential required for chemical processes.

[0042] Thus, according to another broad aspect of the present disclosure, there is provided an energy storage device (e.g., a power supply system) comprising at least one electrochemical cell as defined above and an electrical module for applying a potential difference between an electrode and a counter electrode connectable to the electrode for at least one of charging and discharging the energy storage device, wherein the energy storage device is configured to cause a decrease in the potential difference applied between the electrode and the counter electrode for at least one of charging and discharging the energy storage device due to an interaction of the chiral system with the electrode causing charge rearrangement, spin polarization of the surface, and spin polarization of electrons injected from or into the surface.

[0043] In some embodiments, at least one of the first and second electrolytes includes an active material that is a chiral material.

[0044] In some embodiments, the energy storage device is configured as a battery.

[0045] In some embodiments, the energy storage device is configured as an electrochemical capacitor.

[0046] This technology relates to processes for improving the work function of surfaces coated with chiral molecules, and corresponding uses, particularly in energy storage devices such as batteries with improved charge times, or other electrochemical processes involving, for example, electrochemical cells operating as electrolyzers (e.g., hydrogen, aluminum, chlorine electrolyzers). Thus, in some embodiments, the presently disclosed subject matter relates to methods of use in batteries and the batteries themselves. When electrons flow from one material to another within a battery cell, the spin of such electrons affects the work function and internal resistance. Reducing the work function and internal resistance of batteries and battery components is an important aspect of the overall performance of the battery. In particular, reducing the internal resistance of such energy storage devices can result in more efficient electrochemical reactions, reducing resistivity waste and enhancing the performance of the energy storage device (e.g., capacity, charge time, reduced temperature, etc.). The batteries may be rechargeable or disposable.

[0047] According to another broad aspect of the present disclosure, there is provided a method of using an electrode as defined above in an electrochemical system, the method comprising: interacting between an electrode (i.e., an anode) and an electrolyte of the electrochemical system to induce charge rearrangement, spin polarization of the surface, and spin polarization of electrons injected from or into the surface, thereby lowering the work function of the chiral electrode; and passing a current from the electrode to the electrolyte, wherein the interaction between the chiral electrode and the electrolyte is configured to change the spin state at the electrode-electrolyte interface, thereby optimizing operation of the electrochemical system.

[0048] According to another broad aspect of the present disclosure, a photovoltaic cell module is provided, comprising: at least one photovoltaic cell configured and operable to receive light, convert the energy of the received light into electrical energy, and generate electric power; at least one pair of electrodes configured and operable to electrically couple the photovoltaic cells and collect electric power; and a layer having an electrically conductive surface at least partially supporting a chiral system, the layer being disposed between the at least one photovoltaic cell and the at least one pair of electrodes and configured and operable to enhance the performance and efficiency of the photovoltaic cell module. In this regard, it should be noted that under solar irradiation, excitons are generated in the active region of a photovoltaic cell (e.g., a Si solar cell). To achieve high operating efficiency, charge separation between excited electrons and holes is crucial. This is often achieved by implementing a P / N or P / I / N junction. Therefore, while doping the active region is crucial in all photovoltaic cells, it also creates a loss mechanism due to non-radiative recombination decay in the active region. These scattering effects reduce cell efficiency. The excited electrons migrate to the current collector and pass through an external electrical circuit, generating a current. The electron-hole recombination rate is a crucial factor in the efficiency of a photovoltaic cell. Another loss mechanism occurs due to the overpotential barrier that the charge must cross before entering the electrode / current collector. The novel technology disclosed here can reduce the overpotential of the electrode at the current collector, increasing charge separation efficiency while reducing recombination losses.

[0049] Semiconductors such as silicon are orders of magnitude less conductive than metals. To increase the likelihood that electrons will reach the current collector and, through it, reach the external circuit, most cells use metal-based contacts / current collectors. The top contact often has a grid pattern (due to the need to transfer electricity out of the cell while allowing light into the cell). The bottom contact is often a full metal "sheet." The key design tradeoff in the top contact design is balancing the increased resistive losses associated with a wider grid spacing against the increased shielding caused by a narrower grid spacing. The interface between the semiconductor cell and the metal contact is another parameter that affects contact resistivity, current crowding at the contact edge (an additional resistivity driver), and losses via recombination at the contact. Reducing the resistance at the metal contact / semiconductor interface can lead to more efficient photovoltaic cells with reduced recombination and resistive losses and improved overall cell performance. As electrons flow from the semiconductor to the contact, their spin affects the resistance at the interface. The aligned spins reduce resistivity, allowing more electrons to pass through to the external circuit.

[0050] In this disclosure, we provide contacts and coatings for photovoltaic cell contacts that exhibit improved electron transfer efficiency. The contacts, or portions of the contacts, are made of or coated with chiral systems. Chiral systems enhance spin selectivity through the CISS effect, and aligned spins act to reduce resistivity and therefore electrode overpotential at the current collector. Furthermore, the presence of chiral molecules on both the positive and negative contacts reduces recombination of electron-hole pairs as a result of charge separation. When the positive and negative contacts are chiral, similar charge separation occurs, thus increasing charge separation efficiency while reducing recombination losses.

[0051] In some embodiments, at least one electrode of the photovoltaic cell module comprises a substrate having a conductive surface that at least partially supports a chiral system. The chiral system of the photovoltaic cell module may be as defined above. The substrate of the photovoltaic cell module may be made of at least one of a metal, a chiral conductor, and a semiconductor.

[0052] According to another broad aspect of the present disclosure, there is provided an electrical component including a substrate having a conductive surface at least partially carrying a chiral system, the chiral system being configured to control the work function of the electrical component, and interaction of the chiral system with the electrical component causing charge rearrangement, spin polarization of the surface, and spin polarization of electrons injected from or into the surface, thereby lowering the work function of the electrical component and the internal electrical resistance of the electrical component. The chiral system may be as defined above. The substrate of the electrical component may be made of at least one of a metal, a chiral conductor, and a semiconductor.

[0053] In some embodiments, the electrical component is configured as an electrical switch configured to control the flow of electricity from the energy source.

[0054] In some embodiments, the electrical component is configured as an electrical connector configured to electrically couple multiple electrical circuits.

[0055] In order to better understand the subject matter disclosed herein and to illustrate how it may be carried out in practice, embodiments will now be described, by way of non-limiting example only, with reference to the accompanying drawings, in which: [Brief explanation of the drawings]

[0056] [Figure 1] FIG. 1 is a flow chart illustrating the major steps of a method for controlling the work function of at least one electrode in accordance with the teachings of the presently disclosed subject matter. [Figure 2]FIG. 2 shows the different work functions obtained for different electrodes made from gold, gold coated with a monolayer of L-cysteine, gold coated with a monolayer containing a mixture of the L and D enantiomers of cysteine, and gold coated with a monolayer of 3-mercaptopropionic acid (MPA). [Figure 3] FIG. 3 is a schematic illustration of mechanisms affecting the work function of electrodes and electrode surfaces in accordance with the teachings of the presently disclosed subject matter. [Figure 4] 4A-4B show specific, non-limiting examples illustrating possible uses of electrodes of the presently disclosed subject matter in electrochemical systems, in particular, FIG. 4A shows a schematic diagram of a possible electrochemical cell, and FIG. 4B shows the potential barrier over time for different configurations of the electrochemical cell. [Figure 5] FIG. 5 shows a manufacturing process scheme for coating the active material of a battery with chiral molecules. [Figure 6] Figures 6A-6I show electrode material particles coated with chiral molecules for characterization. In particular, Figures 6A-6D show XPS spectra of S 2p (Figure 6A), N 1s (Figure 6B), Co 2p (Figure 6C), and Ni 2p (Figure 6D) for chiral-A, chiral-B, achiral-C, and untreated NCM811 samples; Figure 6E shows the XRD diffraction peaks of the NCM powder sample in the 2θ range of 10° to 80°; Figures 6F-6I show high-resolution SEM images of the powder samples; Figures 6F-6G show high- and low-magnification images of the chiral-A sample, respectively; and Figures 6H-6I show high- and low-magnification images of the untreated NCM811 sample, respectively. [Figure 7] Figures 7A-7C show electrochemical measurements of the chiral-A, chiral-B, achiral-C, and pristine NCM811 / Li half cells for the IV profiles (Figure 7A), discharge capacity rate profiles (Figure 7B), and cycling stability performance at 1C rate (Figure 7C). All measurements were performed in 1 M LiPF6 EC / EMC (3:7) electrolyte solution at 35 °C. [Figure 8]Figures 8A-8H show post-mortem analysis, Figures 8A-8C show SEM and EDX spectra of the electrodes after cycling at a 1 C rate for Chiral-A, and Figures 8D-8F show SEM and EDX spectra of the electrodes after cycling at a 1 C rate for untreated NCM811. Figure 8G shows a comparison of the XRD patterns of the electrodes before and after cycling for Chiral-A and untreated NCM811 samples, and Figure 8H shows the selective XRD pattern of the (003) plane. [Figure 9] FIG. 9 shows a schematic layout of an electrochemical device containing a gold working electrode coated with a self-assembled monolayer (SAM) of either chiral or achiral molecules. [Figure 10] Figures 10A-10C show spectra obtained by polarization-modulated infrared reflection absorption spectroscopy (PM-IRRAS) to characterize monolayer formation on gold electrodes. In particular, Figure 10A shows the spectra of Au surfaces coated with 3-mercaptopropionic acid (achiral) and L-cysteine (chiral), Figure 10B shows the spectra of various achiral alkanethiols used in the experiment, and Figure 10C shows the spectra of various chiral oligopeptides used in the experiment. [Figure 11] Figures 11A-11C show the oxygen reduction activity of the molecularly coated electrodes. Specifically, Figure 11A shows the current versus potential measured when the electrode was coated with a monolayer of an achiral molecule (achiral 3-mercaptopropionic acid, blue curve) or a chiral molecule (L-cysteine, red curve) in a 0.1 M KOH solution saturated with N2 (dotted curve) and O2 (solid curve). Figures 11B-11C show the current versus potential measured when the electrode was coated with a monolayer of an achiral molecule (1-octadecanethiol) (Figure 11B) and a chiral oligopeptide (L-ala5) (Figure 11C) in a 0.1 M KOH solution saturated with N2 (dotted curve) and O2 (solid curve). [Figure 12] FIG. 12 shows the current versus potential at three electrodes: a commercial Pt / C electrode, an achiral Pt NP electrode, and a chiral Pt NP electrode. [Figure 13]13A-13D show the dependence of oxygen reduction on molecular length. In particular, FIGS. 13A and 13B show the current versus potential curves for achiral (FIG. 13A) and chiral (FIG. 13B) molecular monolayers of various lengths, respectively; and FIGS. 13C and 13D show the onset potential versus molecular length for working electrodes modified with achiral (FIG. 13C) and chiral (FIG. 13D) monolayers of different lengths, respectively. [Figure 14] Figures 14A-14D show the resistive characterization of chemically coated electrodes, specifically the cyclic voltammetry curves obtained for electrodes coated with either achiral (Figure 14A) or chiral (Figure 14C) monolayers; Figures 14B and 14D show the peak current densities for long and short molecules, respectively, for achiral (Figure 14B) and chiral (Figure 14D) molecules. [Figure 15] Figures 15A and 15B show electrochemical impedance spectra of surfaces coated with (Figure 15A) achiral molecules (1-decanethiol, 1-octadecanethiol) and (Figure 15B) chiral molecules (L-ala3, L-ala7) in a three-electrode system; Figure 15C shows the equivalent circuit model employed to fit the electrochemical impedance spectra; and Figure 15D summarizes the Rs and Rct values estimated from the equivalent circuit model. [Figure 16] Figures 16A and 16B show the circular dichroism spectra (Figure 16A) and UV-visible absorption spectra (Figure 16B) of gold (Au) films synthesized using L- or DL-tartaric acid; Figure 16C shows the ORR performance of the synthesized Au thin films. [Figure 17] Figures 17A and 17B show the circular dichroism spectra (Figure 17A) and UV-visible absorption spectra (Figure 17B) of gold nanoparticles (Au NPs) synthesized with L- or DL-cysteine; Figure 17C shows the current versus potential measured with gold nanoparticles (Au NPs) of different chiralities. [Figure 18]Figures 18A-18D show the morphological characterization of Pt nanoparticles (NPs), specifically, Figures 18A and 18C show transmission electron microscopy (TEM) images, and Figures 18B and 18D show the particle size distribution of Pt NPs modified with L-cysteine (Figures 18A, 18B) or DL-cysteine (Figures 18C, 18D). [Figure 19] Figures 19A and 19B show the circular dichroism spectra (Figure 19A) and UV-visible absorption spectra (Figure 19B) of Pt nanoparticles (Pt NPs) synthesized using L- or DL-cysteine; Figure 19C shows the ORR performance of Pt NPs; Figures 19D–19F show the electrochemical properties of Pt catalysts, including cyclic voltammetry (CV) curves of chiral Pt NPs (Figure 19D), achiral Pt NPs (Figure 19E), and a commercial Pt / C catalyst (Figure 19F) in N-saturated 0.1 M KOH. Figure 19G shows the current versus potential measured for platinum nanoparticles (Pt NPs) of different chiralities, with a commercial Pt / C catalyst added for comparison. [Figure 20] Figures 20A-20F show the effect of chiral molecules, specifically, Figure 20A shows the dependence of spin polarization on the length of the chiral oligopeptide; Figure 20B shows the calculated number of electrons transferred, specifically, current versus potential measured for monolayers of L-ala3 and L-ala7 in O2-saturated 0.1 M KOH electrolyte at a scan rate of 50 mV / s; Figure 20C shows the splitting of the spin state of triplet oxygen after interaction with spin-polarized electrons present on the chiral molecule; Figures 20D and 20E show the possible spin states for chiral (Figure 20D) and achiral (Figure 20E) systems; and Figure 20F shows the calculated triplet energy level on oxygen as a function of the distance between the chiral molecule and oxygen. [Figure 21] FIG. 21 illustrates a possible configuration of an energy storage device comprising an electrochemical cell configured as a battery, with each of the battery electrodes comprising a respective substrate having a conductive surface and carrying a respective chiral system according to the principles of the present disclosure. [Figure 22]FIG. 22 shows a possible configuration of a photovoltaic cell module comprising photovoltaic cells, in particular, each of the electrodes of the photovoltaic cells comprising a respective layer having a conductive surface that at least partially retains a chiral system according to the principles of the present disclosure. [Figure 23] Figures 23A and 23B show possible configurations of electrical components comprising a substrate having a conductive surface that at least partially retains a chiral system; in particular, Figure 23A shows a junction field effect transistor (JFET) in which a chiral coating covers the electrodes of the gate, source, and drain terminals; and Figure 23B shows an interconnect comprising a metal, magnetic, or superconductor layer and two contacts / electrodes, with a chiral coating covering the interface between the outer surface of the metal, magnetic, or superconductor layer and the contacts / electrodes. [Figure 24] 24A and 24B illustrate possible configurations of energy storage devices configured as electrochemical capacitors, specifically the electrochemical capacitor of FIG. 24A includes two electrodes separated by an ion-permeable membrane (separator), each of the electrodes coated with a chiral system according to the principles of the present disclosure; and the electrochemical capacitor of FIG. 24B includes two charged conductive plates, one of the plates positively charged and the other of the plate negatively charged, with a dielectric layer separating the conductive plates, each of the conductive plates coated with a chiral system according to the principles of the present disclosure. [Figure 25] Figures 25A and 25B respectively show two possible configurations of an electrochemical cell system, in particular, Figure 25A shows an electrochemical cell configured as a water electrolysis device with two electrodes, an anode and a cathode, both of which carry a chiral system according to the principles of the present disclosure; Figure 25B shows an electrochemical cell configured as a fuel cell, with the two electrodes, an anode and a cathode of the cell, carrying the chiral system described in the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0057] Refer to FIG. 1 showing a method 100 for controlling the work function Wf of at least one surface. The method 100 includes measuring a first work function Wf1 of a first surface at 102, depositing a chiral system on the first surface at 104 to cause a change in the first work function Wf1, and applying a potential difference between the first surface and a second surface at 106 to cause charge transfer between the first surface and the second surface. The interaction between the chiral system and the first surface is configured to cause charge rearrangement, spin polarization of the first surface, and spin polarization of electrons injected from or into the first surface, thereby modifying the work function Wf1f of the first surface. Depositing the chiral system on the first surface at 104 may include chemically bonding the chiral system to the first surface at 104A, such as when bonding a thiol to gold, or physically adsorbing the chiral system to the first surface at 104B, such as when depositing a chiral oxide.

[0058] When the techniques of the present disclosure are implemented to improve an electrochemical process in which the first and second surfaces are utilized as the first and second electrodes and the flow of current between the two electrodes involves an electrochemical reaction and electron transfer between two substances, the method 100 may further include immersing the first surface and the second surface in an electrolyte at 108 before applying the potential difference. In an electrolytic process, since electrical energy is directly converted into chemical energy, the interaction between the chiral first surface (functioning as an electrode) and the electrolyte is configured to change the spin state at the electrode - electrolyte interface, reducing the applied potential difference that would have been applied if the chiral system had not been deposited on the electrode surface, as further illustrated below with respect to FIG. 4B. Thus, when a second work function of the first surface holding the chiral system is measured at 110, a change in the work function of the first surface is observed such that Wf2 < Wf1, that is, the second work function is lower than the first work function.

[0059] Referring to Figure 2, the work function difference measured with a Kelvin probe between a reference electrode and a gold (Au) surface that is uncoated, coated with a monolayer of a chiral molecule (e.g., cysteine), a monolayer containing a mixture of the L- and D-enantiomers of cysteine, or a monolayer of the achiral molecule 3-mercaptopropionic acid (MPA) is shown. More specifically, the work function of the uncoated gold surface is −565 mV, the work function of the gold surface coated with a monolayer of L-cysteine is −305 mV, the work function of the gold surface coated with a monolayer containing a mixture of the L- and D-enantiomers of cysteine is −412 mV, and the work function of the gold surface coated with an achiral molecule is −393 mV. In this regard, it should be noted that although achiral monolayers can change the work function of the electrode surface, they increase the electrode resistance and are therefore less relevant in electrochemical applications. In the case of chiral molecules, the resistance of the chiral film is low due to the CISS effect, and the decrease in work function compensates for the slight increase in resistivity. Therefore, it is clearly shown that the presence of chiral molecules significantly decreases the work function of the electrode surface. The work function of gold coated with a chiral monolayer is the smallest (-305 mV).

[0060] The inventors have found that charge rearrangement occurs in chiral materials when they come into contact with an electrode surface. This charge rearrangement is accompanied by spin polarization. Therefore, binding between the molecule and the substrate requires that the electrons of the substrate have an opposite spin to the spin of the chiral material. The additional energy generated by charge rearrangement is proportional to the degree of spin polarization multiplied by the spin exchange interaction, and is in addition to the general chemical energy associated with the bond, stabilizing the bond.

[0061] See FIG. 3 , which illustrates an example of an electrode 300 for use in the electrochemical processes of the present disclosure. When a chiral system 304 is supported by a substrate having a conductive surface 302, the chiral system 304 becomes charged and spin-polarized. The substrate 302 may be made of a metal and / or semiconductor, such as Pt, gold, silicon, or Cu. To bind to the surface, the spins of electrons on the surface 302 must be aligned opposite to the spins of electrons belonging to molecules and located near the substrate. Thus, the chiral layer 304 induces spin polarization in the outermost atoms. Therefore, electrons injected from or into the surface 302 are spin-polarized, thereby allowing them to travel smoothly through the interface and the chiral molecules 304. In this way, the chiral system 304 is configured to control the work function Wf of the electrode surface 302, such that the interaction of the chiral system 304 with the substrate 302 causes charge rearrangement, spin polarization of the surface 302, and spin polarization of electrons injected from or into the surface 302. The stabilization energy resulting from the bond is the fraction of spin-polarized electrons multiplied by the spin exchange energy.

[0062] See FIG. 4A, which shows an example of an electrochemical cell 400 using an electrode of the presently disclosed subject matter. The electrochemical cell 400 comprises an electrode 402 made of a Zn substrate coated with chiral molecules and immersed in an aqueous ZnSO4 electrolyte solution. The electrochemical cell 400 also comprises a counter electrode 404, which is connected to the chiral electrode 402 via an electrical module 406 configured to apply potential energy between the electrodes 402 and 404. The counter electrode 404 is made of Cu and is configured to be immersed in the aqueous CuSO4 electrolyte solution. The aqueous ZnSO4 and CuSO4 electrolyte solutions are separated by a permeable (e.g., porous) membrane that prevents rapid mixing but allows ion diffusion. The membrane may be a conventional membrane or may comprise a substrate with a conductive surface that at least partially retains the chiral system. In the left cell, Zn 2+ The extra electrons left behind when the ions are ejected from the Zn substrate can flow through the external circuit to the right electrode, where they are transported to the Cu2+ ions, Cu 2+ The ions become "discharged," i.e., converted to Cu atoms at the surface of the copper electrode. The net reaction is the oxidation of zinc by copper(II) ions. The reaction can be started or stopped by connecting or disconnecting the two electrodes. The reaction can be forced to proceed in the non-spontaneous, or reverse, direction by connecting a battery or other current source to the two electrodes. The chiral molecules may be deposited on the zinc electrode 402, as in this example, or alternatively, on the copper electrode 404 or both. The presence of the chiral molecules on the Zn substrate allows for a lower voltage to be applied to force the reaction and generate current.

[0063] When the electrochemical cell 400 is used as a power supply system (e.g., a ZnCu battery) in which current is generated from spontaneous redox reactions, a significant reduction in the potential barrier can be measured when the zinc electrode 402 (i.e., the cathode) is covered with a chiral coating, thereby significantly improving charging times. Typically, a power supply system comprises multiple electrochemical cells interconnected with each other (in series and / or parallel).

[0064] FIG. 4B illustrates the potential over time for electrochemical cells with different configurations, showing the charging time and potential barrier for batteries with different configurations. The first curve 408A shows the measured potential when both the anode and cathode are coated with α-helical chiral molecules. In this regard, it should be noted that although coating both electrodes can be beneficial for reducing the potential barrier, as in this specific, non-limiting example, coating both electrodes may not reduce the potential barrier depending on the specific relative potentials of the two electrodes. The second curve 408B shows the measured potential when only the anode is coated with chiral molecules. The third curve 408C shows the measured potential when only the cathode is coated with chiral molecules, and the fourth curve 408D shows a control measurement without molecular aggregates. This figure clearly shows that coating the cathode with a chiral coating significantly lowers the potential barrier for initiating the electrochemical process, as indicated by the increased potential obtained in the electrochemical cell in which the cathode was coated with the chiral molecule compared to the electrochemical cell in which the anode and cathode were uncoated (from about 1.090 V to about 1.094 V).

[0065] The following section details how chiral molecular coating can improve the cathode performance of lithium-ion batteries.

[0066] To test the effect of CISS on Li-ion batteries, we adsorbed chiral AHPA molecules onto the active materials of the batteries. Hereinafter, the term "active material" refers to the material responsible for the reversible electrochemical reactions that occur during charge-discharge cycles. The active material may be present in the positive and negative electrodes or in the electrolyte. The active material may be an inherently chiral material or a material coated with a chiral material. The electrolyte may be solid or liquid and may or may not have chiral properties. The flow process for coating the cathode material with chiral molecules is shown in Figure 5. Commercially available cathode powder LiNi purchased from TARGRAY-USA 0.8 Mn 0.1 Co 0.1O2 (NMC811) was UV-treated and then placed in a 1 mM ethanol solution of L-α-helical polyalanine (AHPA), 3008.71 g / mol. A total of 3 mg of APHA was used to coat 4 g of NMC811 powder. During the coating process, the reactor was gently shaken to homogenize the suspension. After drying the sample under a nitrogen atmosphere for 24 hours, the coated NMC811 powder (Chiral-A) was obtained. For the Chiral-B sample, the same 1 mM concentration of coated NMC811 was used, but the sample was washed with the chiral solution using 2 μm filter paper rather than left to dry in solution (Chiral-B). A control sample (Achiral-C) was prepared using the same process as Chiral-A, but with an achiral molecule (12-mercaptododecanoic acid, Sigma-Aldrich, 232.38 g / mol). The proposed procedure is extremely simple and can be easily scaled up for battery production.

[0067] The crystal structure of the sample was identified using X-ray diffraction (XRD, D8 advance, Bruker). The chemical composition of the coating layer of the cathode material was analyzed by X-ray photoelectron spectroscopy (XPS, Thermo Scientific K-Alpha) under Al Kα irradiation. X-ray photoelectron spectroscopy (XPS) measurements were performed using a 5600 Multi-Technique System (PHI, USA) at UHV (2.5 × 10 -10 The sample was irradiated with an Al Kα monochromatic light source (1486.6 eV) and the emitted electrons were analyzed with a spherical capacitor analyzer using a 0.8 mm slit aperture. The morphology of the sample was analyzed using a high-resolution scanning electron microscope (HRSEM, FEI, Magellan 400 Lis). The morphology and microstructure of the sample were detected with a field-emission scanning electron microscope (Nova Nano SEM 450, FEI) and a high-resolution transmission electron microscope (HRTEM, Tecnai G2 F20, FEI).

[0068] Figures 6A-6D show the XPS spectra of the Chiral-A, Chiral-B, Achiral-C, and untreated NCM811 samples. These results suggest that organic matter was adsorbed onto the NCM particles. Figure 6A shows the presence of organic matter in the treated sample, indicated by the 2S peak. Figure 6B shows a typical XPS spectrum of N 1s. A peak associated with pyrroline N at 400.1 eV is observed, which can be associated with the amino group in the chiral polypeptide. In the high-resolution XPS spectrum of Ni 2p (Figure 6C), in addition to two satellite peaks at 879.6 eV and 861.5 eV, two other peaks at 873.5 eV and 855.9 eV correspond to Ni 2p, respectively. 1 / 2 and Ni 2p 3 / 2 In addition, Figure 6D shows Co 2p at 796.6 eV and 780.9 eV. 1 / 2 and Co 2p 3 / 2 These two large peaks were found in all samples, including chiral-A, chiral-B, achiral-C, and untreated NCM811. 2+ and Co 3+ The results indicate the presence of

[59] . Considering the nominal calculated length of the AHPA is 5.4 nm and the achirality is 2.6 nm, the transition metal (TM) content of Ni and Co in uncoated NMC particles is three times higher than that of coated samples, as expected with the coating

[60] . Comparing the binding energy values of untreated and chiral-coated NMC811 cathodes, no shift was observed (Table 2 below). XPS analysis indicates that the chiral coating on the NMC811 cathode does not change the interfacial composition or the oxidation state of the NMC811 core.

[0069] Figure 6E shows the XRD diffraction peaks of the NCM powder samples in the 2θ range from 10° to 80°. All diffraction peaks are properly indexed to the respective crystal planes of the hexagonal structure with space group R-3m. As can be seen from the diffraction, the adsorption of chiral molecules does not change the properties of the NCM, and the same is true for achiral molecules. From the XRD patterns of the as-prepared powders, a highly crystalline layered structure can be observed in all four samples. All diffraction peaks, along with the space group, are indexed to the hexagonal α-NaFeO structure, and there is no obvious change in the XRD patterns of the coated samples and the untreated NCM, indicating that the crystalline structure of the cathode materials is similar before and after surface modification. The results also indicate the absence of impurities in the NCM powder samples, suggesting that the chiral molecule (L-α helix polyalanine (AHPA)) and the achiral molecule (12-mercaptododecanoic acid (MDA)) on the NCM particle surface are present in a low, amorphous state due to the nature of a thin coating not detected by XRD.

[61] Typically, the intensity ratio of the (003) to (104) diffraction peaks can be used to determine the order of cations in NCM materials, and the ratio value is inversely proportional to the cation order. Layered structures with a low degree of cation mixing are more stable when the ratio is greater than 1.2. The calculated I(003) / I(104) ratios for the four samples, Chiral-A, Chiral-B, Achiral-C, and Untreated NCM811, are 1.35, 1.46, 1.35, and 1.58, respectively. Additionally, the split double peaks of (006) / (102) and (108) / (110) indicate the degree of order in the crystalline structure of the material unaffected by the chiral-protected cathode material. Both results fully confirm the layered structure of the material. In summary, we conclude that the layered structure of the NCM sample can be well retained after chiral-protection coating on untreated NCM811.

[0070] HRSEM images of Chiral-A and untreated NMC811 are shown in Figures 6F-6I. Figures 6F-6G show high- and low-magnification images of the Chiral-A sample, respectively, and Figures 6H-6I show high- and low-magnification images of the untreated NMC811 sample, respectively. These HRSEM images indicate that the chiral and achiral coatings on the NMC811 particles were not affected or degraded by the adsorption process, and the spherical structure of the particles was preserved. Elemental maps of individual particles show that the coating was uniform across the particle surface. The results are summarized in Table 1 below. TIFF2025526225000003.tif60170

[0071] Electrochemical testing was performed using a 2032 coin-type test cell. A cathode composed of polyvinylidene fluoride (PVDF) binder (10 wt%), acetylene carbon black (10 wt%), and chiral-coated NCM811 active material (80 wt%) was dispersed in N-methylpyrrolidone (NMP) to form a uniform slurry. This slurry was cast onto aluminum foil, dried on a hot plate, and then dried overnight at 110 °C under vacuum to evaporate the NMP solvent. The dried cathode was cut into a 12 mm diameter circle for use as the cathode electrode of a LIB coin cell. The active material loading mass was approximately 2.34 mg. Lithium foil (200 μm thick) and a Celgard PP2500 polypropylene membrane were used as the anode and separator, respectively. A commercially available electrolyte solution, LP-57, containing 1 M LiPF in an ethylene carbonate-ethyl methyl carbonate mixture (3:7; volume:volume), was used as the electrolyte. Coin cells (CR-2032) were assembled in an argon-filled glove box, and the moisture and oxygen contents were kept below 0.1 ppm. The cycle and rate performance were measured at room temperature (30 °C) using a Neware battery tester under galvanostatic conditions within the voltage windows of 2.8 to 4.3 V and 2.8 to 4.5 V (vs. Li / Li+), respectively. Cyclic voltammetry (CV) was performed within the range of 2.8 to 4.5 V, with a 0.1 mV s -1At a potential scan rate of 0.01–10, electrochemical impedance spectroscopy (EIS) tests were performed with a perturbation amplitude voltage of 5 mV. 5 The measurements were performed on a Biologic (VSP) system in the frequency range of 100 Hz.

[0072] The IV profiles (vs. Li counter electrode) of uncoated NMC811 (pristine) and coated NMC811 electrodes are shown in Figure 7A. Both the uncoated and coated NMC811 samples exhibit two voltage plateaus at approximately 3.7 V and 4.2 V. The overlapping voltage profiles in Figure 7A reveal two main observations. First, the average overpotential obtained with the chiral-coated NMC811 is lower relative to the achiral-coated or uncoated NMC811. Second, the cells using the chiral-coated NMC exhibit higher specific discharge capacities than the achiral-coated or uncoated NMC.

[0073] The performance of the samples was evaluated using coin-type CR2032 lithium half-cells at rates ranging from 0.1 C (10-hour discharge) to 4 C (15-minute discharge) at voltages ranging from 2.8 to 4.3 V. The initial charge-discharge formation voltage profiles of all four samples at a 0.1 C rate are shown in Figure 7A. The specific discharge capacities of the Chiral-A, Chiral-B, Achiral-C, and untreated NMC cathodes are 217.7 ± 1, 209, 207, and 206 mAh / g, respectively. As can be seen from the figure, the rate performance is improved by the surface coating. At low C rates (0.1 C and 0.2 C), the Chiral-A sample NMC811 delivered a larger specific discharge capacity (5–10 mAh / g) than the other samples.

[0074] More significant improvements in discharge capacity were observed at higher rates of 1C, 2C, and 4C. The specific discharge capacity of the chiral-A sample showed an average increase of 8.7% at 4C, an average increase of 6% ± 0.2% compared to the untreated sample. The chiral-B and achiral-C samples showed smaller increases of 5.7% and 4.6% at 4C, an average increase of 3% and 1.8%, respectively. These results demonstrate that coating NMC811 generally improves the kinetics of the Li intercalation / deintercalation process, as both chiral and achiral coatings improved performance. This suggests that the organic coating can prevent breakdown of the electrolyte solution at the NMC surface by forming a thick passivation layer that slows the Li intercalation / deintercalation kinetics. However, the cells with the chiral coating outperformed the cells with the achiral coating. This demonstrates that, in addition to physical protection, the chiral coating improves the discharge / charge process.

[0075] Overall, the electrochemical performance of all three protected NMC cathode materials, Chiral-A, Chiral-B, and Achiral-C, demonstrates superior rate capability compared to untreated NCM811. The chiral coating's improvement in the charge-discharge process leads to a stable configuration and lower electrical resistivity within the cell. The lower the electrical resistivity of the coin cell, the lower the implied voltage for a given discharge rate, thereby resulting in a more stable voltage discharge region. Compared to the untreated NCM811 cathode, the electrochemical performance, in terms of discharge specific capacity, is improved for all three molecularly protected NCM811 cathode samples, Chiral-A, Chiral-B, and Achiral-C. Upon cycling, all samples (coated and uncoated) underwent reasonable capacity fade. The discharge capacity retention rates of the Chiral-A, Chiral-B, and Achiral-C samples are 84.5%, 89%, and 92%, respectively, after 100 cycles at a 1C rate. An uncoated sample of pristine NMC811 achieved a discharge capacity retention rate of 91%. Long-term stabilization of the NMC811 interface using chiral or achiral coatings has not been observed. These results indicate that the protective coating layer prevents direct contact between the electrolyte and the NCM811 particles, which stabilizes the electrochemical reactions at the interface and SEI interfacial layer. The thickness of the coating significantly affects the electrochemical performance of the cathode material. Thin coating layers (1–3 nm) are insufficient to protect NCM811, and their ability to suppress side reactions at the interface is low, as observed here in the Chiral-B and Achiral-C samples. Thicker coating layers (approximately 10 nm) improve stability and performance, as shown in the Chiral-A sample, and allow Li transport through the chiral molecular protective layer. + By lengthening the diffusion path of Li + Suppress the movement of

[0076] Finally, the morphology and composition of the cathode materials were further investigated using high-resolution scanning electron microscopy (HR-SEM) and EDX spectroscopy after cycling the electrodes, as shown in Figures 8A–8F. The treated Chiral-A electrode exhibits no cracking or structural degradation on the core NCM811 particles after successive electrochemical charge-discharge cycles. In the case of the untreated sample, clear degradation of the primary particles from the macro-sized secondary particles is observed, along with slight crack formation and erosion. The EDX spectra of the cathodes of the Chiral-A (Figure 8C) and untreated NCM811 (Figure 8F) samples confirm that the NCM811 composition is maintained after successive charge-discharge cycles of the cathode. Therefore, we found that the decay was similar in all cases, given that longer cycles with higher capacities were obtained. The X-ray diffraction patterns of the chiral protective coated Chiral-A and untreated NCM811 electrodes, shown in Figures 8G and 8H, indicate no structural or phase changes after successive cycles.

[0077] Thus, we demonstrated that modifying the surface of NMC811 material using chiral coating technology can significantly improve the electrochemical performance of lithium-ion cells. NMC811 electrodes coated with chiral molecules exhibited lower voltage hysteresis and better rate performance, with a 9% improvement in capacity at a 4C discharge rate and an average 6% improvement in rate capability measurements. Meanwhile, the achiral sample showed only a 4.6% capacity improvement at 4C, with an average improvement of 2%. These results demonstrate that the chiral-induced spin selectivity (CISS) effect plays an important role in the charge-discharge process. The capacity retention of the chiral-treated cell was only 85% after 100 cycles, compared to 92% for the achiral-treated cell and 91% for the untreated cell.

[0078] See Figure 9, which shows a schematic layout of an electrochemical setup containing a gold working electrode coated with a self-assembled monolayer (SAM) of either chiral or achiral molecules. We used an electrochemical assay method in which O2 was bubbled through the electrochemical cell and the reduction current was monitored. The electrochemical cell was assembled with a Pt counter electrode, an Ag / AgCl reference electrode, and a working electrode, which could be either chiral or achiral. In the first phase of the experiment, we synthesized chiral cysteine and the oligopeptide, SH-(CH2)2-NH-(Ala-Aib), as shown in Table 2 below. n The self-assembled monolayers (SAMs) of -COOH (n=3, 5, 7, 8, 11 are designated as L-ala3, L-ala5, L-ala7, L-ala8, and L-ala11, respectively) or the achiral molecules 3-mercaptopropionic acid and SH-(CH2) n A 100 nm thick gold film coated with a monolayer of -CH3 (n = 3, 7, 9, 13, 17) was used. TIFF2025526225000004.tif111170

[0079] The solution used to prepare the monolayer was first bubbled with Ar for over 30 min. Achiral alkanethiol molecules were dissolved in ethanol to form a 1 mM solution. Chiral oligopeptides were dissolved in 2,2,2-trifluoroethanol (≥99%, Sigma-Aldrich) to form a 1 mM clear solution. Au film electrodes were fabricated on single-crystal silicon wafers by electron beam evaporation using a Cr (10 nm) / Au (100 nm) layer combination. Prior to adsorption, the surfaces were cleaned by boiling in acetone and ethanol for 10 min each, followed by UV / ozone treatment for 15 min, and then immersion in ethanol for 40 min. These surfaces were then dried under a nitrogen stream and immediately immersed in a solution of thiol molecules for 72 h.

[0080] The monolayer formation was characterized by infrared spectroscopy using a polarization-modulated infrared reflection absorption spectrometer (PM-IRRAS), and the respective spectra are shown in Figures 10A-10C. The spectra were recorded using a Nicolet 6700 FTIR instrument equipped with a PEM-90 photoelastic modulator (Hinds Instruments, Hillsboro, OR). Each spectrum was acquired by integrating 2000 scans with the sample mounted at a Brewster angle of 80°. The spectra of the monolayers of 3-mercaptopropionic acid (MPA) and L-cysteine (Figure 10A) exhibit a characteristic peak at 3236 cm, which is attributed to the OH stretching mode of the carboxyl group. -1 Also, 2927cm -1 Strong peaks at 1726 cm belong to the asymmetric and symmetric CH stretching frequencies of the -CH group. -1 The carbonyl (C=O) stretching mode signature of the carboxyl group is also present at 1569 cm. -1 Note that the monolayer shows a weak vibrational band at 1000 kJ / cm2, which is assigned to the NH bending vibration of the NH group. In contrast, we did not observe this peak in the 3-mercaptopropionic acid monolayer (Figure 10A), which is consistent with its molecular structure (Table 1 above). Apart from the NH vibration of the NH group, the intensities of the other peaks in both L-cysteine and MPA are almost the same, indicating that their surfaces are similarly covered.

[0081] For alkanethiol-coated Au surfaces, 2851 cm -1 From 2965cm -1 The strong peaks in the range of -100 to -1000 are assigned to the asymmetric and symmetric CH stretching frequencies of the -CH groups present in the alkyl chain (Figure 10B). In addition, the intensity of these peaks increases with increasing alkyl chain length from 1-butanethiol to 1-octadecanethiol.

[0082] Figure 10C shows the PM-IRRAS spectrum of the oligopeptide monolayer. -1The strong peak at 1542 cm is the typical stretching mode of the C-O bond (amide-I), while the peak at 1542 cm -1 The peaks can be assigned to the NH in-plane bending mode and the C-N stretching mode (amide-II). Furthermore, the intensity of these two characteristic peaks increases with the length of the oligopeptide, demonstrating that the Au surface was successfully coated with different chiral molecules.

[0083] Electrochemical measurements were performed using a three-electrode electrochemical cell with an Ag / AgCl reference electrode and a platinum wire as the counter electrode. The working electrode was a Au film modified with different molecules (see above). Electrochemical data were recorded at room temperature using a potentiostat (PalmSens4) electrochemical workstation. Potentials were measured against an Ag / AgCl (3 M NaCl) reference electrode and subsequently calibrated against a standard reversible hydrogen electrode (RHE). The working electrode was kept stationary during all measurements.

[0084] Electrochemical reduction was performed using 0.1 M aqueous KOH at pH = 13. Oxygen was bubbled for at least 30 min before measurements began to ensure saturation. All applied potentials were scaled relative to a standard reversible hydrogen electrode (RHE).

[0085] Under the alkaline conditions of these experiments, two reduction pathways are generally considered possible

[62] : TIFF2025526225000005.tif26170

[0086] Figures 11A–11C show the oxygen reduction activity of molecularly coated electrodes. Figure 11A shows current versus voltage plots for electrodes coated with SAMs of achiral 3-mercaptopropionic acid (blue) or chiral L-cysteine (red) in 0.1 M KOH saturated with N2 (dotted curve) and O2 (solid curve). The onset potential is defined as the potential at which the current reaches a value of 0.1 mA / cm2, as shown by the dashed line. The current density was normalized with respect to the geometric area of the working electrode. Figures 11B and 11C show current versus potential plots measured in 0.1 M KOH saturated with N2 (dotted curve) and O2 (solid curve) when the electrodes were coated with monolayers of an achiral molecule (1-octadecanethiol) (Figure 11B) and a chiral oligopeptide (L-ala5) (Figure 11C).

[0087] The striking difference in current densities in O2-saturated and N2-saturated solutions indicates that both the chiral and achiral-functionalized electrodes exhibit oxygen reduction activity. It is quite clear that the onset potential for reduction is shifted by approximately 0.25 V, even though the two molecules are the same length and very similar in structure (Figure 11A). Note that the barrier to ORR is lower at more positive potentials, and that the coating of organic molecules on the Au surface results in an onset potential that is lower than that seen with uncoated Au (see Figure 12).

[63]

[0088] Figure 12 shows the current versus potential for three electrodes: a commercially available Pt / C electrode, an achiral Pt NP electrode, and a chiral Pt NP electrode. The current versus potential was measured at a scan rate of 50 mV / s using commercially available uncoated Pt / C, achiral Pt NP, and chiral Pt NP. As clearly shown in this figure, coating the electrode with a chiral coating lowers the potential barrier for initiating the electrochemical process, as evidenced by the increase in potential. Therefore, electrodes fabricated using the teachings of the novel technology of the present disclosure can lower the electrode's overpotential and improve charge separation efficiency while reducing recombination losses.

[0089] Figures 13A and 13B show current versus voltage curves for ORR when electrodes are coated with achiral (Figure 13A) and chiral (Figure 13B) molecules of different lengths. As can be seen in Figure 13C, for achiral molecules, the onset potential decreases with increasing molecular length, indicating a higher reaction barrier as the SAM thickness increases. In stark contrast, for chiral molecules (Figure 13D), the onset potential increases with increasing molecular length, indicating a lower reaction barrier as the SAM thickness increases. The higher barrier observed for achiral molecules is consistent with the increasing electrical resistance of the molecule with increasing length and the decreasing O solubility of alkanes with increasing molecular length. We investigated whether a lower potential (higher overpotential) is required to achieve the same current density observed in thick films as in thin films. Surprisingly, however, for SAMs containing chiral molecules, the potential increases with length, even though the resistance of the molecule is known to increase with length and the diffusion of O2 through the layer to the electrode is thought to decrease with molecular length. The unexpected decrease in the ORR reaction barrier with increasing oligopeptide length correlates with the improved spin filtering of the oligopeptide with increasing length (see below).

[0090] To confirm that the different behavior is not due to significant length differences between the two molecules or the quality of the SAM, current versus potential curves were plotted using ferri / ferrocyanide (Fe(CN)6) instead of oxygen. 3- / 4- The redox couple was measured in 0.1 M KCl aqueous electrolyte solution, and therefore the redox couple in solution is not affected by whether the molecule is chiral or achiral. 3- / 4- Cyclic voltammetry (FIGS. 14A-14D) and electrochemical impedance spectra (FIGS. 15A-15D) were collected in an aqueous solution containing 1000 sachets of ...

[0091] Figures 14A–14D show the resistive characteristics of chemically coated electrodes. Cyclic voltammetry curves were obtained on electrodes coated with either an achiral (Figure 14A) or chiral (Figure 14C) monolayer. Curves are shown for short molecules (1-decanethiol (Figure 14A) and L-ala3 (Figure 14C)) and long molecules (1-octadecanethiol (Figure 14A) and L-ala7 (Figure 14C)). The inset shows the curve for the long molecule with the current axis expanded. The dashed lines (Figures 14A and 14C) indicate the voltage at which the peak current density was obtained. Panels shown in Figures 14B and 14D show the peak currents for the long and short molecules, respectively, for the achiral (Figure 14B) and chiral (Figure 14D) molecules. Note that the ratio of the peak currents is very similar for these two types of molecules.

[0092] Achiral ferricyanide has low spin d 5 complex, and ferrocyanide is a low-spin d 6 Considering the coordination complex, no spin polarization effect is expected for the electron exchange in this redox pair. In this case, surfaces coated with the shorter molecules (1-decanethiol in Figure 14A and L-ala3 in Figure 14C) exhibit significantly higher redox peak currents than the longer molecules (1-octadecanethiol in Figure 14A and L-ala7 in Figure 14C), regardless of whether the molecules are chiral or achiral.

[0093] These findings are confirmed by impedance measurements, which show that impedance increases with length for both types of molecules, as shown in Table 3 below and in Figures 15A-15D. TIFF2025526225000006.tif51170

[0094] Figures 15A and 15B show electrochemical impedance spectra of surfaces coated with (Figure 15A) achiral molecules (1-decanethiol, 1-octadecanethiol) and (Figure 15B) chiral molecules (L-ala3, L-ala7) in a three-electrode system. Figure 15C shows the equivalent circuit model employed to fit the electrochemical impedance spectra. s is the sum of the electrode resistance and the electrolyte resistance, CPE is the double layer capacitance, and R ct represents the charge transfer resistance, and W s represents the Warburg impedance within the diffusion component, and Figure 15D shows the R estimated from the equivalent circuit model. s and R ct From the Nyquist curves (Fig. 15A), a much smaller semicircle is observed for 1-decanethiol than for 1-octadecanethiol, indicating that the charge transfer process at the electrode coated with the short molecule is more efficient. From Fig. 15D, the R values for the 1-decanethiol and 1-octadecanethiol systems are s The calculated values of are almost the same, while R ct It can be seen that the value of σ decreases significantly with molecular length. Similar results were obtained for the chiral L-ala3 and L-ala7 (Figures 15B and 15D).

[0095] We further investigated whether chiral enhancement also occurs when the electrode is made of a material with an intrinsically large spin-orbit coupling. We fabricated chiral Au films by electrodeposition in the presence of tartrate ions in the deposition solution using the following procedure. Briefly, 0.2 M L- or DL-tartaric acid, 0.02 M Na3Au(SO3), 0.42 M Na2SO3, and 0.42 M Na2SO3 were added to 10 mL of water and the pH was adjusted to 8. A three-electrode electrochemical cell was used for deposition, in which a 15 nm Au-coated quartz substrate served as the working electrode. A saturated calomel electrode (SCE) and a Pt wire served as the reference and counter electrodes, respectively. A constant potential of -0.63 V was applied for 5 min during deposition. After electrodeposition, the electrodes were washed with water and used for ORR experiments.

[0096] The handedness of the deposited chiral Au films was determined by chiral tartrate ions. Circular dichroism (CD) measurements were performed using a Chirascan spectrometer from Applied Photo Physics, England. All spectra were measured using a scan range of 185–700 nm, a time of 0.5 s per point, a step size of 1 nm, and a bandwidth of 1 nm. For solution samples, a quartz cuvette with a 2 mm optical path was used. CD spectra of Au films containing L- or DL-tartaric acid were measured on 0.5 mm-thick quartz substrates and are shown in Figure 16A. Figure 16B shows the UV-visible absorption spectra of gold (Au) films synthesized using L- or DL-tartaric acid.

[0097] The synthesized chiral Au thin film on a quartz substrate was directly used as a working electrode for the oxygen reduction reaction. For Au and Pt NPs, equal amounts of chiral or achiral NPs were dispersed in water by vigorous stirring and ultrasonication. 8 μL of the NP solution was dropped onto a glassy carbon electrode (GCE; diameter 3 mm, manufactured by ALS Co., Ltd., Japan). The amount of metallic Pt loaded was 1 cm2. 2 The concentration of NPs was maintained at 42 μg per electrode (confirmed by ICP-MS). After evaporating water for 3 h at room temperature, 4 μL of 0.05 wt % Nafion solution was dropped onto the electrode surface to coat and stabilize the NP aggregates on the electrode surface. The GCE loaded with such NPs was immersed in the solution as the working electrode. ORR activity was measured in O2-saturated 0.1 M KOH under oxygen purging at room temperature at a sweep rate of 50 mV / s.

[0098] The onset potential obtained with the "chiral gold film" was improved compared to the Au electrode coated with a chiral monolayer, as shown in Figure 16C (compare Figure 3A). Furthermore, the ORR onset potential of the chiral metallic Au film was 90 mV higher than that of the film prepared with a racemic mixture of tartaric acid (-0.1 mA / cm in Figure 16C). 2 The onset potentials at 1000 kJ / s are 0.49 V and 0.58 V for the racemic and chiral Au films, respectively, and an improvement of approximately 20% was obtained.

[0099] Similar chirality enhancement was observed for Au nanoparticles containing L- or D-cysteine (Figures 17A-17C). Chiral gold nanoparticles were synthesized according to the procedure reported in

[74] . Typically, cubic Au seeds were first synthesized and dispersed in a 1 mM aqueous solution of cetrimonium bromide (CTAB). 0.8 ml of 100 mM CTAB and 0.2 ml of 10 mM chloroauric acid trihydrate were added to 3.95 ml of deionized water to form the growth solution. The cubic seed solution was then added to the growth solution, followed by 100 μM cysteine 20 min later. The sample was placed in a 30 °C bath for 2 h, and the pink solution gradually turned to a highly scattering blue. The solution was centrifuged twice to remove any unreacted reagents.

[0100] Figures 17A and 17B show the circular dichroism (Figure 17A) and UV-visible absorption (Figure 17B) spectra of gold nanoparticles (Au NPs) synthesized with L- or DL-cysteine. Figure 17C shows the current versus potential measured using gold nanoparticles (Au NPs) of different chiralities. The curves were recorded in an O2-saturated 0.1 M KOH solution at room temperature with a sweep rate of 50 mV / s. The current density was normalized based on the geometric area of the GCE.

[0101] Considering the large spin-orbit coupling of Au, the increased ORR onset potential of chiral Au NPs compared to achiral Au NPs, as seen in Figure 17C, confirms the additional contribution of spin-polarized electrons induced by the chiral molecules. As will be shown below, this contribution must go beyond merely relaxing the spin selection rules.

[0102] To investigate the effect of chirality on materials used in fuel cells, we synthesized platinum nanoparticles (Pt NPs) using the L- and D-enantiomers of cysteine as ligands. Platinum nanoparticles (Pt NPs) were synthesized using chloroplatinic acid hydrate and L- or DL-cysteine as ligands, with water as the reaction medium. To 718 μL of DI water, 82 μL of 122 mM chloroplatinic acid, 200 μL of 7.5 mM L- or DL-cysteine, and 200 μL of 200 mM NaBH4 were added.

[0103] Figures 18A-18D show the morphological characterization of Pt nanoparticles (NPs). In particular, Figures 18A-18C show transmission electron microscopy (TEM) images, and Figures 18B and 18D show the particle size distribution of Pt NPs modified with L-cysteine (Figures 18A, 18B) or DL-cysteine (Figures 18C, 18D). The scale bars in Figures 18A and 18C are 20 nm. TEM images were taken using an FEI (Philips) Tecnai T12 operated at 120 kV.

[0104] For the circular dichroism measurements shown in Figure 19A, the cysteine concentration was increased to 50 mM. After 2 hours of magnetic stirring under a N2 atmosphere at room temperature, a brownish, transparent nanoparticle dispersion was obtained. The synthesized nanoparticles were analyzed after thorough purification by rinsing the NPs with E-pure water. Precipitation was achieved by adding a large amount of isopropanol, followed by centrifugation at 10,000 rpm for 20 minutes. Figure 19B shows the UV-visible absorption spectra of Pt nanoparticles (Pt NPs) synthesized using L- or DL-cysteine.

[0105] When a racemic mixture of L- and D-cysteines was used, it was designated as achiral NPs. L-cysteine-modified Pt NPs showed a clear CD signal in the NP absorption spectrum region, whereas racemic cysteine-modified NPs showed no CD signal (Figures 19A and 19B). Again, the onset potential of the chiral Pt NPs far exceeded that of the achiral counterpart (Figure 19C). As a comparative benchmark, measurements were also performed on a commercially available Pt / C catalyst (nominal 20% Pt on carbon black).

[0106] To normalize the oxygen reduction current, electrochemically active surface area (ECSA) was measured using the hydrogen adsorption / desorption method for platinum under alkaline conditions

[64] . A 0.1 M aqueous KOH solution was first purged with O, and a continuous stream of argon was introduced into the cell to maintain an inert atmosphere. CV curves were recorded at a scan rate of 50 mV / s from 0.0 V to 1.2 V vs. RHE and are shown in Figures 19D–19F for chiral Pt NPs (Figure 19D), achiral Pt NPs (Figure 19E), and a commercial Pt / C catalyst in N-saturated 0.1 M KOH (Figure 19F), respectively. ECSA was determined by integrating the hydrogen adsorption charge over the CV and calculated as follows: ECSA = Q des / (m×Q ref ), in the formula, Q des is the total charge of H desorption, and Q ref is the charge density associated with monomolecular adsorption of H2 on a unit weight of platinum, and m is the amount of platinum loaded on the electrode.

[0107] After normalizing the oxygen reduction current by the ECSA of each catalyst, the chiral Pt NPs exhibit higher onset potentials in the ORR than the prior art Pt / C catalyst on an equivalent Pt mass basis, as shown in FIG. 19G.

[0108] Previous studies have shown that the coupling of electron spin direction to the chiral axis of a molecule significantly exceeds thermal energy at room temperature

[65] , and that chiral molecules act as spin filters

[66] . A measure of the spin-dependent filtering is provided by the spin polarization ratio P, defined as: TIFF2025526225000007.tif11170, I α is the electron current whose electron spin is parallel to its velocity, and I β is an electron flow in which the electron spin is oriented antiparallel to the electron velocity. The effect of chiral molecules on ORR efficiency can be clarified by examining the correlation between the length of the chiral molecule and the spin polarization of the electrons transmitted through it. Figure 20A shows the dependence of the spin polarization on the length of a chiral oligopeptide, modified with permission from

[67] . Conduction is higher for electrons whose spins are aligned parallel to the velocity, and the magnitude of the spin polarization increases from 30% to 45% as the length of the oligopeptide increases

[67] . Based on the spin polarization results, it is possible to calculate the dependence of the current on the spin polarization during the reduction process.

[0109] The number of electrons transferred in the oxygen reduction process can be estimated by comparing the spin polarization shown in Figure 20A with the current-voltage profiles shown in Figures 14A-14D (particularly Figures 14C and 14D), which consider the cases of L-ala3-mediated and L-ala7-mediated ORR. If the rate-limiting step of ORR involves the transfer of a single electron, the ratio of the spin polarizations through the two peptide membranes should be equal to the ratio of the observed currents through the membranes. However, if a multielectron process is present (n electrons transferred in the reaction step), the ratio should be a product of the respective spin effects. This theory suggests that the following equation can be used to calculate n: TIFF2025526225000008.tif13170On the left side, the spin polarization of L-ala7 (SP ala7 = 45 ± 3%) and SP ala3 = L-ala3 (31±3%) and current density I ala7 and I ala3 The product of I and I represents the spin-polarized current passing through each film. ala7 and I ala3is estimated by the method shown in Figure 20B. To obtain two current densities at the same overpotential, we first took the tangent to the maximum slope of the reduction current and extrapolated it to zero current density to obtain the intersection point (a and a'). Then, we shifted the intersection point by a negative potential of 0.1 V (b and b'). The current density at this potential was calculated as I ala7 or I ala3 (points with arrows); that is, I ala7 =-0.16mA / cm 2 and I ala3 =-0.13mA / cm 2 ). Using these values in equation (4), we find that n = 2.8. Therefore, based on the spin polarization from Figure 20A and the equation above, we conclude that 2.9 ± 1.5 electrons are involved in the rate-determining step of the reduction process.

[0110] The oxygen reduction reaction requires four electrons (4e - ) pathway

[68] , the electron transfer number is approximately 2.35 based on the current densities on the L-ala11 and Pt surfaces. In addition, two electrons of oxygen (2e - ) reduction has been reported on polycrystalline Au surfaces [69,70], so the similar current densities for Au and L-ala11 indicate that a predominantly two-electron process occurs on the chiral oligopeptide-coated surface. This value is consistent with our calculations above from the spin polarization.

[0111] Therefore, this calculation suggests that 2.9 ± 1.5 electrons are involved in the rate-determining step of the reduction, and a similar number of electrons was obtained by evaluating the current density between the platinum surface and the chiral monolayer (Figure 12). This finding suggests that when the monolayer-modified Au surface serves as the working electrode, oxygen reduction occurs via a two-electron mechanism, as described above (Eq. (2) above).

[0112] Regardless of the exact mechanism of oxygen reduction, in the first step, O2 2- or HO2 -At least two electrons are required to generate α(1)α(2)

[62] . When considering spin statistics, the projection of the O2 molecule's spin onto the chiral axis arising from the monolayer becomes important as the O2 molecule approaches the SAM. Figure 20C shows the splitting of triplet oxygen spin states due to interaction with spin-polarized electrons present on the chiral molecule. For O2 with one and two unpaired electrons, three possible spin states are possible: α(1)α(2), β(1)β(2), and [α(1)β(2) + β(1)α(2)] / √2. In the case of a chiral oligopeptide, the two electrons injected from the monolayer have the same spin projection onto the molecular axis, i.e., their state is αα. Therefore, the reaction barrier is affected by both an entropic factor (related to spin statistics) and an enthalpic factor resulting from the stabilization of the β(1)β(2) state of O2 by spin-exchange interactions with polarized electrons on the chiral molecule.

[0113] Figures 20D and 20E show the possible spin states for a chiral system (Figure 20D) and an achiral system (Figure 20E). In an achiral system, the two electrons can have four possible configurations, only one of which can lead to a reaction. In a chiral system, there is only one possible configuration, and the electrons are tightly bound to the molecular frame, so this is the only configuration that can lead to a reaction.

[0114] In chiral molecules, the spin direction is aligned with the molecular axis. However, on oxygen, three degenerate spin states split as the molecule approaches the chiral monolayer; that is, as in the case of a magnetic field, the spin states split and the states β(1) and β(2) are stabilized. When oxygen interacts with the chiral monolayer (when their electron clouds overlap), the spin-exchange effect strengthens these interactions (Figure 20C). This effect lowers the enthalpy barrier, resulting in more efficient spin injection from the monolayer into the oxygen system. Furthermore, the alignment of the O2 spin state with the chiral monolayer reduces the entropic contribution to the free-energy barrier (Figures 20D and 20E). In the case of an achiral monolayer, the monolayer has four possible spin states: αα, ββ, αβ, and βα, of which only one allows efficient electron transfer to the oxygen (hence, the reaction probability is only one-fourth). Furthermore, the spins on the achiral monolayer are not coupled to the molecular frame, so they do not split the oxygen spin state and the enthalpy barrier is not lowered.

[0115] Model calculations support the mechanism described above. Theoretical simulations treat chiral molecules as chains of nuclear sites, each of which contains a single electronic level and is coupled to both nearest and next nearest neighbors via both elastic and inelastic spin-orbit interactions [70,71].

[0116] The inelastic component in this model consists of nuclear vibrations that couple to the electronic structure through both spin-independent and spin-dependent electron-vibration coupling. These two components arise from nuclear motions that modify the nuclear confinement potential and are therefore related to both the overlap matrix elements involved in the tunneling rate between nuclei as well as the spin-orbit interactions in the structure. Theoretical simulations were performed using a model for a chiral molecule based on a chain of nuclear sites, each of which is connected to a single electronic level (ε m), which couples to nearest neighbors via both elastic (t0) and inelastic (t1) hopping and to next nearest neighbors via both elastic (λ0) and inelastic (λ1) spin-orbit coupling. See references (24) and (25). The inelastic component in this model is the nuclear vibration, mode ω, which couples to the electronic structure through both spin-independent (t1) and spin-dependent (λ1) electron-vibration coupling. m These two components arise from nuclear motions that modify the nuclear confinement potential V(r) and therefore contribute to both the overlap matrix elements involved in the tunneling rate between nuclei and also to the spin-orbit interaction in the structure. Chiral molecules are attached at one end to a metal reservoir. TIFF2025526225000009.tif9170

[70] and

[71] , while the opposite end is It is connected to the O2 molecule through a direct exchange interaction v in the form of TIFF2025526225000010.tif9170, where Ψ † N (Ψ N ) represents the creation (annihilation) spinor at the molecular site N, σ is a vector of the Pauli matrix, and S O2 =S1 + S2 is the spin operator of the O2 molecule, where S 1,2 represents the spin 1 / 2 operator for two unpaired electrons. The exchange integral v is calculated as a function of the distance R between the chiral molecule and the O2 molecule using the formula for the exchange between electrons in an H2 molecule: TIFF2025526225000011.tif30170, In the formula, j0=e 2 / 4πε0, e is the electron charge, ε0 is the vacuum permittivity, S'(s) = -S(s), s = R / a0, a0 is the Bohr radius, γ is Euler's constant, and E1(x) is the exponential integral.

[0117] For the simulations, we model the chiral molecule with 6 turns of 8 ions per turn and the following parameters (units of t = 40 meV): μ is the chemical potential of the entire system, and Γ represents the binding strength between the metal reservoir and the chiral molecule. All simulations are performed at T = 300 K, as summarized in Table 4 below. TIFF2025526225000012.tif28170

[0118] One end of the chiral molecule is bound to the metal reservoir, and the opposite end interacts with an O2 molecule through a direct exchange interaction v, which is calculated as a function of the distance R between the chiral molecule and the O2 molecule using the equation for the exchange between electrons of an H2 molecule (see Figure 20F below)

[70] . TIFF2025526225000013.tif9170, where Ψ † N (Ψ N ) represents the creation (annihilation) spinor at the molecular site N, σ is a vector of the Pauli matrix, and S O2 is the spin operator of the O2 molecule. The assembly of the metal, chiral molecule, and O2 molecule constitutes an open system in which the charge distribution and associated spin polarization of the chiral molecule, as well as the magnetic moment of the O2 molecule, are determined by self-consistent computation using non-equilibrium Green's functions. Figure 12F illustrates the effect of helical interactions on the energy of the spin metastable state of the O2 molecule by showing the calculated triplet energy levels on oxygen presented as a function of the distance between the chiral molecule and oxygen.

[0119] Although based on a simple model, this calculation indicates a splitting of the triplet state sublevels that can be several hundred meV (tens of kcal / mol). These findings are consistent with recent studies showing enhanced oxygen reduction efficiency with magnetic electrodes [72,73], likely due to spin alignment of the injected electrons. The proposed mechanism should be relevant for two-electron simultaneous reductions and even for sequential processes, as long as the second electron is injected on a timescale shorter than the spin depolarization time.

[0120] Given that the CISS effect can enhance the rate of multi-electron reaction steps by reducing the number of accessible spin channels, it is intriguing to speculate on its implications for the glucose oxidation process, which involves six oxygen molecules and 24 electrons. Due to the large number of possible multi-electron transfer steps in such a complex redox scheme, the reduction in activation entropy due to spin filtering could potentially enhance the overall rate by more than an order of magnitude in chiral biomolecules. Homochirality in living organisms implies a reduction in entropy that increases the organism's Gibbs free energy. The respiratory process and its strong benefits from homochirality, due to the small number of possible spin states (low entropic reaction barrier), may help drive this selection. This novel mechanism by which spin-filtered electrons increase the overall reaction efficiency may partly explain why life has so consistently preserved chirality throughout evolution.

[0121] This disclosure demonstrates that controlling spin in multi-electron transfer processes such as ORR results in two contributions to reaction rate. The first corresponds to the constraint on spin selectivity, allowing the reaction to occur on the triplet potential energy surface. The second is to reduce the number of states available for reaction, thereby lowering the entropy barrier. Our results suggest that control over electron spin is an important property for catalysts used in important oxygen-related reactions, reducing overpotentials and increasing current densities.

[0122] Refer to FIG. 21, which illustrates a possible configuration of an energy storage device 500 including an electrochemical cell configured as a battery 502. The battery 502 includes, among other things, an electrode 504A and a counter electrode 504B. Each of the electrodes 504A and 504B includes a corresponding substrate 506A and 506B having a conductive surface and supporting a corresponding chiral system 508A and 508B. The chiral system 508A and / or 508B may be at least one of an organic material and an inorganic material with chiral properties. As described above, the chiral-induced spin selectivity (CISS) effect reduces the resistance of the electrode interface by aligning electron spins, dramatically lowering the overpotential required for chemical processes. When electrons flow from one material to another within a battery cell, the spin of such electrons affects the work function and internal resistance. Reducing the work function and internal resistance of batteries and battery components is an important aspect of the overall performance of the battery. In particular, lowering the internal resistance of such energy storage devices can result in more efficient electrochemical reactions, reducing waste resistivity and enhancing the performance (e.g., capacity, charging time, temperature reduction, etc.) of the energy storage device. The battery may be a rechargeable battery or a disposable battery. In this specific and non-limiting example, the electrode 504A is configured to interact with a first electrolyte 510A of the battery 502, and the counter electrode 504B is configured to interact with a second electrolyte 510B that interacts with the first electrolyte. If the first and / or second electrolytes 510A and 510B are solid, the electrode 504A and the counter electrode 504B are positioned to contact the respective electrolytes. If the first and / or second electrolytes 510A and 510B are liquid, the electrode 504A and the counter electrode 504B are immersed in the respective electrolytes. In this case, the first and second electrolytes 510A and 510B are in fluid communication with each other. These two electrolytes may be made of the same material. However, the battery configuration is not limited to this configuration, and electrodes 504A and 504B may be immersed in the same electrolyte. The interaction between the chiral electrode and the electrolyte changes the spin state at the electrode-electrolyte interface, thereby optimizing the battery's operation.In this specific, non-limiting example, electrolytes 510A and 510B are separated by a permeable (e.g., porous) membrane / separator 512 that prevents them from mixing but provides chemical communication between electrolytes 510A and 510B, i.e., allows ions to diffuse through to maintain the electrical neutrality of battery 502.

[0123] The battery 502 further comprises an electrical module 514 for applying a potential difference between the electrode 504A and the counter electrode 504B to at least one of charge and discharge the energy storage device 500.

[0124] The chiral systems 508A and 508B are configured to control the work function of the corresponding electrodes 504A and 504B. Interaction of the chiral systems with the electrodes causes charge rearrangement, spin polarization of the corresponding surfaces 508AS and 508BS, and spin polarization of electrons injected from or into the corresponding surfaces 508AS and 508BS, lowering the work function of the corresponding electrodes 504A and / or 504B, the potential for initiating electrochemical processes, and the internal electrical resistance of the electrodes.

[0125] 21 , the left electrode 504A is positive, meaning that electrons are injected into the surface, while the right counter electrode 504B is negative, meaning that electrons are injected from the surface. The energy storage device 500 is configured such that the interaction of the chiral systems 508A and 508B with the corresponding electrode substrates 506A and 506B causes a decrease in the potential difference applied between the electrode 504A and the counter electrode 504B by the electrical module 514 for at least one of charging and discharging the energy storage device 500 due to charge rearrangement, spin polarization of the surfaces, and spin polarization of electrons injected into or from the corresponding surfaces 508AS and 508BS.

[0126] See FIG. 22 , which illustrates a possible configuration of a photovoltaic cell module 600 comprising at least one photovoltaic cell 602 configured and operable to receive light, convert the energy of the received light into electrical energy, and generate electrical power. The photovoltaic cell 602 comprises, among other things, a pair of electrodes / current collectors, 604A and 604B, which are configured and operable to electrically couple the photovoltaic cell 602 and collect electrical power. The photovoltaic cell 602 further comprises upper and lower junction layers, 608A and 608B, respectively, an absorber layer 610 (made of a semiconductor material), and an anti-reflective layer 612. An external electrical circuit 614 supplies the generated electrical current resulting from excited electrons generated in the photovoltaic cell 602. In this specific, non-limiting example, the electrodes 604A and 604B each comprise a corresponding layer 606A and 606B having an electrically conductive surface that at least partially retains a chiral system. However, the configuration of the photovoltaic cell module 600 is not limited to this configuration. The coating with the chiral system may be applied to the electrodes 604A and 604B as in the present example, or to the bonding layers 608A and 608B, or to both the electrodes and the bonding layers.

[0127] During typical operation of photovoltaic cell 602, when light strikes the solar cell, electrons in absorber layer 610 are excited from a lower energy "ground state," where they are bound to specific atoms in the solid, to a higher energy "excited state" where they can move through the solid. Junction-forming layers 608A and 608B induce a built-in electric field that imparts collective motion to the electrons, which can flow through electrical contact layers 604A and 604B into an external circuit 614 where they can do useful work.

[0128] The electron-hole recombination rate is one of the critical factors in the efficiency of a photovoltaic cell and is a loss mechanism in the active region. Another loss mechanism occurs due to an over-potential barrier that charge must cross before entering the electrodes / current collectors 604A and 604B. Layers 606A and 606B, located between the bonding layers 608A and 608B and the metal electrodes / current collectors 604A and 604B, respectively, are constructed and operable to enhance the performance of the photovoltaic cell by lowering the electrode over-potential at the current collectors, improving charge separation efficiency while reducing recombination losses.

[0129] Reference is made to Figures 23A and 23B, which illustrate possible configurations of electrical components comprising a substrate having a conductive surface at least partially carrying a chiral system. Figure 23A shows a junction field-effect transistor (JFET) 700 in which a chiral coating 702 covers the gate, source, and drain terminal electrodes. Figure 23B shows an interconnect comprising a metallic, magnetic, or superconductor layer 710 and two contact / electrodes 712, with the chiral coating 702 covering the interface between the outer surface of the metallic, magnetic, or superconductor layer 710 and the contact / electrodes 712. In both components (700 and 750), the chiral system 702 is configured to control the work function of the electrical component; interaction of the chiral system 702 with the corresponding surface of the electrode causes charge rearrangement, spin polarization of the surface, and spin polarization of electrons injected from and into the electrode surface, lowering the work function of the electrical component and the internal electrical resistance of the electrical component. It should be noted that chiral coating 702 may be applied to the gate, source, and drain terminal electrodes, as in the example of Figure 23A, or to the semiconductor substrate in contact with the corresponding electrodes, or to both the electrodes and the semiconductor substrate. Also, with respect to the example of Figure 23B, chiral coating 702 may be applied to the surface of contact / electrode 712, or to the outer surface of layer 710, or to both the electrode and layer. JFET 700 may be configured as an electrical switch to control the flow of electricity from an energy source, and interconnect 750 may be configured to electrically couple multiple electrical circuits.

[0130] Reference is made to Figures 24A and 24B, which illustrate possible configurations of energy storage devices 900 and 950 configured as electrochemical capacitors. The electrochemical capacitor 900 of Figure 24A includes two electrodes 902A and 902B separated by an ion-permeable membrane (separator) 904, an electrolyte 906 ionically connecting the electrodes, and a power source 908. When the electrodes are polarized by an applied voltage 908, ions in the electrolyte 906 form electric double layers 910A and 910B that are opposite in polarity to the polarity of the corresponding electrode. For example, a positively polarized electrode has a layer of anions at the electrode / electrolyte interface with a charge-balancing layer of cations adsorbed to the negative layer. The reverse is true for a negatively polarized electrode. The double layers 910A and 910B act roughly as the dielectric layers in a conventional capacitor, and the efficiency of charging and discharging these electric double layers directly affects the capacitance realized by the storage device 900.

[0131] According to some embodiments of the novel technology of the present disclosure, each one of the electrodes 902A and 902B is coated with a chiral system 912 configured to cause a reduction in the potential difference applied between the electrodes 902A and 902B for at least one of charging and discharging the energy storage device 900 due to an interaction between the chiral system 912 and the corresponding electrode, which causes charge rearrangement, spin polarization of the electrode surface, and spin polarization of electrons injected into or from the electrode surface. Alternatively or additionally, the ion-permeable separator 904 may comprise a substrate having a conductive surface that at least partially retains the chiral system. The chiral separator may improve charge separation through a spin filtering effect.

[66] Therefore, to improve charge separation, the energy storage device of the present disclosure may include a chiral electrode and / or at least one chiral separator.

[0132] 24B includes two charged conductive plates 952A and 952B, where one of the plates (e.g., 952A) is positively charged and the other of the plates (e.g., 952B) is negatively charged. Capacitor 950 also includes a dielectric 954 and a connecting wire 956 that carries the current that is generated and used to charge and discharge capacitor 950. Dielectric 954 can act as a separator that separates the negative and positive charges on the two charged conductive plates 952A and 952B. According to some embodiments of the novel technology of the present disclosure, each one of the conductive plates 952A and 952B is coated with a chiral system 958 configured to cause a decrease in the potential difference applied between the conductive plates 952A and 952B for at least one of charging and discharging the energy storage device 950 due to an interaction between the chiral system 958 and the corresponding conductive plate causing charge rearrangement, spin polarization of the corresponding conductive plate surface, and spin polarization of electrons injected into or from the corresponding surface.

[0133] Reference is made to FIGS. 25A and 25B, which illustrate two possible configurations of electrochemical cell systems 1000 and 1100, respectively. In this specific, non-limiting example, the electrochemical system 1000 of FIG. 25A includes an electrochemical cell 1010 configured as a water electrolyzer that uses electricity, e.g., by applying a voltage from a power source 1014, to electrolyze water into oxygen and hydrogen gas. However, the electrochemical cell systems of the present disclosure are not limited to such a configuration, and other solid-state or liquid electrolytic devices may be used instead. In this example, the hydrogen gas thus released can be used as hydrogen fuel or recombined with oxygen to create oxyhydrogen gas for welding and other applications. The electrodes of the electrochemical cell 1000, an anode 1012A and a cathode 1012B, are constructed in accordance with the principles of the present disclosure. Both electrodes 1012A and 1012B contain a chiral system 1016 as described herein and may be immersed in water, which acts as the electrolyte in this specific, non-limiting example. The electrolyte may also be solid, with the electrodes being placed in contact with the solid electrolyte. The interaction of the chiral electrode with water alters the spin state at the electrode-electrolyte interface, thereby optimizing the operation of the electrochemical system 1010. The electrochemical system 1100 of FIG. 25B includes an electrochemical cell configured as a fuel cell 1110 that converts the chemical energy of a fuel into electricity. The fuel cell 1110 includes, among other things, two electrodes, an anode 1112A and a cathode 1112B, a specially designed electrolyte 1116 that is permeable to ions but not electrons, and a load 1114 that carries the electrical current generated by the fuel cell 1110. The electrodes of the fuel cell 1110, the anode 1112A and the cathode 1112B, are constructed in accordance with the principles of the present disclosure. Both electrodes 1112A and 1112B contain a chiral system 1118 as described herein. The interaction of the chiral electrodes 1112A and 1112B with the electrolyte 1116 is configured to change the spin state at the electrode-electrolyte interface, thereby optimizing the operation of the electrochemical system 1100.

Claims

1. A method for controlling the work function of at least one surface, Measuring the first work function of the first surface, Depositing a chiral system on the first surface to cause a change in the first work function, Applying a potential difference between the first surface and the second surface to cause charge transfer between the first surface and the second surface, To measure the second work function of the first surface that maintains the chiral system, Includes, The second work function is lower than the first work function, and A method wherein the interaction between the chiral system and the first surface is configured to cause a rearrangement of charges, spin polarization of the surface, and spin polarization of electrons injected from or into the first surface, thereby modifying the work function of the first surface.

2. The method according to claim 1, wherein depositing the chiral system on the first surface includes chemically bonding the chiral system to the first surface or physically adsorbing the chiral system to the first surface.

3. The method according to claim 1, wherein the chiral system comprises at least one organic and inorganic substance having chiral properties.

4. The method according to claim 3, wherein the chiral system comprises at least one of the following chiral organic materials: polypeptides, oligopeptides, amino acids, proteins, DNA, helicenes, chiral polymers, or any combination thereof, or the following chiral inorganic materials: chiral oxides, chiral metals, and chiral crystals, or any combination thereof.

5. The method according to claim 1, wherein the chiral system is configured as a single-layer or multilayer structure that acts as a layer that improves charge separation.

6. The method according to claim 5, wherein the chiral system includes a self-assembled monolayer of the chiral molecule or chiral biomolecule.

7. The method according to claim 1, wherein, if the first surface is configured as an electrode and is operable, and the second surface is configured as a counter electrode and is operable, the method further comprises interacting at least one chiral coated surface used as an electrode and another surface as a counter electrode with an electrolyte before applying the potential difference, wherein the interaction between the chiral coated surface and the electrolyte is configured to change the spin state at the electrode-electrolyte interface.

8. An electrode for use in an electrochemical process, comprising a substrate having a conductive surface that holds a chiral system, wherein the chiral system is configured to control the work function of the electrode, the control of the work function of the electrode is by applying a potential difference between the conductive surface and a second surface to cause charge transfer between the conductive surface and the second surface, and the interaction between the chiral system and the conductive surface causes charge rearrangement, spin polarization of the conductive surface, and spin polarization of electrons injected from or into the conductive surface to reduce the work function of the electrode, the potential for initiating the electrochemical process, and the internal electrical resistance of the electrode.

9. At least one of the following: The chiral system includes at least one organic and inorganic substance having chiral properties; The chiral system comprises at least one of the following chiral organic materials: polypeptides, oligopeptides, amino acids, proteins, DNA, helicenes, chiral polymers, or any combination thereof, or the following chiral inorganic materials: chiral oxides, chiral metals, and chiral crystals, or any combination thereof; The chiral system is configured as a single layer or a multilayer structure; The chiral system is chemically bonded to the conductive surface or physically adsorbed thereto; The electrode is made of at least one of metal, chiral conductor, and semiconductor; The electrode is configured as a light absorber. The electrode according to claim 8, characterized by...

10. The electrode according to claim 8, wherein the chiral system is configured as a single layer or a multilayer structure, and the chiral system includes a self-assembled monolayer of the chiral molecules.

11. The chiral system comprises at least one of the following chiral organic materials: polypeptides, oligopeptides, amino acids, proteins, DNA, helicenes, chiral polymers, or any combination thereof, or the following chiral inorganic materials: chiral oxides, chiral metals, and chiral crystals, or any combination thereof; The electrode is configured as a light absorber; The electrode comprises at least one layer of light absorber; The chiral system comprises at least one layer of light absorber having chiral properties; The electrode according to claim 8, wherein the electrode includes light-absorbing nanoparticles bonded to the electrode via the chiral system.

12. A method of using an electrode according to any one of claims 8 to 11 in an electrochemical system, comprising: causing an interaction between the electrode and an electrolyte in the electrochemical system to cause charge rearrangement, spin polarization of the conductive surface, and spin polarization of electrons from or injected into the conductive surface, thereby reducing the work function of the chiral electrode; and passing an electric current from the electrode to the electrolyte, wherein the interaction between the electrode and the electrolyte is configured to change the spin state at the electrode-electrolyte interface, thereby optimizing the operation of the electrochemical system.

13. An electrochemical cell system comprising an electrochemical cell containing at least a first electrolyte and a chiral electrode configured as an electrode having a surface with a controlled work function according to any one of claims 8 to 11, wherein the chiral electrode is configured to hold the chiral system and to interact with the first electrolyte, and the interaction between the chiral electrode and the first electrolyte is configured to change the spin state at the electrode-electrolyte interface, thereby optimizing the operation of the electrochemical cell system.

14. The electrochemical cell system according to claim 13, further comprising a counter electrode connectable to the chiral electrode and configured to interact with a second electrolyte that is chemically in communication with the first electrolyte, wherein potential energy can be applied between the chiral electrode and the counter electrode.

15. The electrochemical cell system according to claim 14, wherein the counter electrode comprises a substrate having a conductive surface that at least partially maintains a chiral system.

16. The electrochemical cell system according to claim 15, wherein the chiral system of the counter electrode comprises at least one organic and inorganic substance having chiral properties.

17. The electrochemical cell system according to claim 15, wherein the chiral system of the counter electrode comprises at least one of the following: chiral organic materials: polypeptides, oligopeptides, amino acids, proteins, DNA, helicenes, chiral polymers, or any combination thereof; or the following chiral inorganic materials: chiral oxides, chiral metals, and chiral crystals, or any combination thereof.

18. At least one of the following: The chiral system is configured as a single layer or a multilayer structure; The chiral system is chemically bonded to the surface of the electrode, or physically adsorbed thereto; The chiral electrode is made of at least one of a metal, a chiral conductor, and a semiconductor. The electrochemical cell system according to claim 13, characterized by the above.

19. The electrochemical cell system according to claim 18, wherein the chiral system is configured as a single layer or a multilayer structure, and the chiral system includes a self-assembled monolayer of the chiral molecules.

20. At least one of the following: The first and second electrolytes are made of the same material; The electrochemical cell system further comprises a diaphragm configured to separate the first electrolyte and the second electrolyte. The electrochemical cell system according to claim 14, characterized by the above.

21. The electrochemical cell system according to claim 14, further comprising a diaphragm configured to separate the first electrolyte and the second electrolyte, wherein the diaphragm comprises a substrate having a conductive surface that at least partially retains a chiral system.

22. At least one of the following: The chiral system of the chiral electrode includes at least one organic and inorganic substance having chiral properties; The chiral system of the chiral electrode includes at least one of the following: chiral organic materials: polypeptides, oligopeptides, amino acids, proteins, DNA, helicenes, chiral polymers, or any combination thereof; or chiral inorganic materials: chiral oxides, chiral metals, and chiral crystals, or any combination thereof; The chiral system of the chiral electrode is configured as a single-layer or multi-layer structure; The chiral system of the chiral electrode is chemically bonded to the surface of the substrate, or is physically adsorbed thereto; The substrate of the chiral electrode is made of at least one of metal, chiral conductor, and semiconductor. The electrochemical cell system according to claim 21, characterized by...

23. The electrochemical cell system according to claim 21, wherein the chiral system of the chiral electrode is configured as a single layer or a multilayer structure, and the chiral system includes a self-assembled monolayer of the chiral molecule.

24. The electrochemical cell system according to claim 13, configured to be immersed in an oxygen-containing solution and operable to promote electron transfer from the electrode to oxygen and reduce the overpotential of the oxygen reduction reaction.

25. Energy storage device comprising at least one electrochemical cell as described in claim 13, and an electrical module for applying a potential difference between the chiral electrode and a counter electrode connectable to the chiral electrode for at least one of charging and discharging the energy storage device, wherein the energy storage device is configured to cause a decrease in the potential difference applied between the chiral electrode and the counter electrode for at least one of charging and discharging the energy storage device, due to an interaction between the chiral system and the chiral electrode causing charge rearrangement, spin polarization of the conductive surface, and spin polarization of electrons injected from or into the conductive surface.

26. At least one of the following: At least one of the first and second electrolytes contains an active material that is a chiral material; The energy storage device is configured as a battery; The energy storage device is configured as an electrochemical capacitor. An energy storage device according to claim 25, characterized by the above.

27. A photovoltaic cell module comprising: at least one operable photovoltaic cell configured to receive light, convert the energy of the received light into electrical energy, and generate power; at least one pair of operable electrodes configured to electrically couple the photovoltaic cell and collect the power; and a layer having a conductive surface that at least partially maintains a chiral system, wherein the layer is positioned between the at least one photovoltaic cell and the at least one pair of electrodes, and is operable, configured to enhance the performance of the photovoltaic cell module. A photovoltaic cell module in which at least one electrode of the pair of electrodes is configured as an electrode according to any one of claims 8 to 11.

28. An electrical component comprising a substrate having a conductive surface that at least partially retains a chiral system, wherein the chiral system is configured to control the work function of the electrical component, and the interaction between the chiral system and the electrical component causes a rearrangement of charges, spin polarization of the conductive surface, and spin polarization of electrons injected into or from the conductive surface, thereby reducing the work function and internal electrical resistance of the electrical component.

29. At least one of the following: The chiral system includes at least one organic and inorganic substance having chiral properties; The chiral system comprises at least one of the following chiral organic materials: polypeptides, oligopeptides, amino acids, proteins, DNA, helicenes, chiral polymers, or any combination thereof, or the following chiral inorganic materials: chiral oxides, chiral metals, and chiral crystals, or any combination thereof; The chiral system is configured as a single layer or a multilayer structure; The chiral system is configured as a monolayer or multilayer structure including a self-assembled monolayer of the chiral molecules; The chiral system is chemically bonded to the conductive surface of the substrate, or is physically adsorbed thereto. The electrical component according to claim 28, characterized by...

30. The electrical component according to claim 28 or 29, wherein the substrate is made of at least one of a metal, a chiral conductor, and a semiconductor.

31. The electrical component according to claim 28, configured as at least one of the following: an electrical switch configured to control the flow of electricity in an energy source; and an electrical connector configured to electrically couple a plurality of electrical circuits.

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