92results about How to "Good electrochemical reversibility" patented technology

The invention relates to an all-vanadium flow battery double-function negative electrode, wherein a carbon material is adopted as a substrate, a Bi-containing electro-catalyst is modified on the surface of the substrate, the Bi-containing electro-catalyst is one or more than two selected from a Bi elementary substance, Bi2O3, a Bi halide and a Bi metal salt, the Bi halide is bismuth fluoride, bismuth trichloride, bismuth bromide, or bismuth iodide, and the Bi metal salt is bismuth sulfate, bismuth nitrate, bismuth phosphate, bismuth formate or bismuth acetate. According to the present invention, the electrode is suitable for the negative electrode of the all-vanadium flow battery, the electrocatalysis activity and the electrochemical reversibility of the electrode material on the V<2+> / V<3+> oxidation reduction reaction can be substantially improved, and the charge transfer resistance can be reduced; and the high hydrogen evolution overpotential is provided so as to inhibit the occurrence of the hydrogen evolution reaction and prolong the service life of the battery.

The invention relates to an electrochemical probe humidity sensor and a relative production, which comprises a humidity sensitive material with room temperature ion liquid, at least two electrodes, an electrochemical probe containing an oxidization reduction couple, a power supply, a current meter and a signal circuit. The oxidization reduction couple is dissolved in ion liquid, with reversible process. The invention is characterized in that the invention uses room temperature ion liquid as the sensitive film of humidity, which has dissolved reversal oxidization reduction couple as the electrochemical probe. The invention uses the cooperation of water molecule and room temperature ion liquid film, to affect the electrochemical reaction current of the oxidization reduction couple to realize humidity detection. The inventive humidity sensor has stable property, high sensitivity, simple structure and low cost or the like.

The present invention discloses an application of carbon nanofiber and a metal composite electrode in a flow battery. An electrode material uses a mixture of high-molecular polymer and metallic salt as a precursor, nanofiber is made by a static electricity spinning method, and then carbon nanofiber is made after performing high-temperature carbonization processing on the nanofiber, wherein a diameter of the carbon nanofiber is 100-1000 nm, a diameter of a metal particle is 2-100 nm, and a mass fraction of metal / the carbon nanofiber is 1%-50%. The carbon nanofiber / metal composite electrode prepared by a preparation method has an excellent electrocatalytic activity and electrochemical reversibility when used in the flow battery, and has the advantages that the preparation method is simple, the working procedure is fewer, the raw material is readily available, the price is low and the like.

A difunctional negative electrode for an all-vanadium redox energy storage battery negative electrode includes a carbon matrix material and a Bi-containing electro-catalyst modifying the surface of the carbon matrix material. The negative electrode is suitable for being used as the negative electrode of the all-vanadium redox energy storage battery, can greatly improve the electrocatalytic activity and electrochemical reversibility of an electrode material on a V<2+> / V<3+> redox reaction, and decreases the charge transfer resistance; and the negative electrode has high hydrogen evolution overpotential, can inhibit a hydrogen evolution reaction, and prolongs the work life of the battery. The difunctional negative electrode improves the voltage efficiency and energy efficiency of the all-vanadium redox energy storage battery, so the working current density of the battery is improved, and the weight, the size and the cost of the battery with same output power are greatly reduced.

The invention relates to a composite membrane counter electrode used for dye-sensitized solar cells (DSSC) and a preparation method thereof, solving the problem that platinum counter electrodes of the existing DSSC have high preparation cost. The composite membrane counter electrode of the invention comprises a conductive substrate, a carbon material membrane and a polypyrrole membrane. The preparation method of the invention comprises the following steps: first preparing electrophoretic liquid of the carbon material and then electrophoretically depositing the carbon material membrane on the conductive substrate; preparing electrodeposition liquid of pyrrole and depositing the polypyrrole membrane on the carbon material membrane by cyclic voltammetry to obtain the carbon material / polypyrrole composite membrane counter electrode. The composite membrane counter electrode of the invention has good catalytic performance, good electrochemical stability, high conductivity and low preparation cost. The photoelectric conversion efficiency of the DSSC based on the composite membrane counter electrode of the invention reaches 4.267%, which is equivalent to that of the existing DSSC based on the Pt counter electrodes.

The invention relates to an anode material being suitable for an aqueous metal ion battery and a preparation method for the same. The anode material contains bismuth oxide and is a nano bismuth oxide array thin film, which is formed by oriented growth of bismuth oxide nano sheets on a metal substrate. The bismuth oxide nano sheets are vertically, uniformly and densely distributed on the metal substrate in an array structure, or that bismuth oxide powder is uniformly mixed with a conductive additive and a binder to form a film on the metal substrate. The anode material is suitable for many types of aqueous batteries, including aqueous lithium ion batteries, aqueous sodium ion batteries, aqueous potassium ion batteries, aqueous magnesium ion batteries, aqueous calcium ion batteries, aqueous strontium ion batteries, aqueous barium ion batteries, aqueous aluminum ion batteries, etc. The aqueous metal ion battery based on the anode material has high capacity, good charging / discharging platform, and high electrochemical reversibility.

The invention relates to an aqueous zinc ion single liquid flow battery system, which comprises a single battery or electric pile formed by over two single batteries in series connection, and an electrolyte solution equipped liquid storage tank. The single battery includes an anode and a cathode, the solute of the electrolyte solution is composed of a zinc ion-containing soluble salt and a soluble salt containing lithium ions and / or sodium ions, and the solvent is water. The anode active material is one of Li or / and Na ion embedded Mn oxide, Co oxide, Ni oxide and Fe oxide or a mixed oxide of more than two of the oxides, and the cathode is a sedimentary type electrode. The anode reaction of the battery adopts intercalation and deintercalation reaction of lithium ions or / and sodium ions, and has higher electrochemical reversibility than the zinc ion intercalation and deintercalation reaction of zinc ion liquid flow batteries. The cathode of the battery adopts zinc deposition dissolution, and compared with the lithium ion and / or sodium ion intercalation and deintercalation reaction of aqueous lithium ion battery cathodes, has higher reversibility, lower price and better cyclic stability.

The invention discloses a porous carbon nanofiber electrode used for a redox flow battery, and a preparation method of the porous carbon nanofiber electrode. The electrode is 20-500[mu]m in thickness and formed by porous carbon nanofibers with diameter of 50-500nm; the porous carbon nanofiber electrode is prepared by the steps of taking a high-molecular polymer as a precursor, preparing into nanofibers through electrostatic spinning, and then performing high temperature carbonization and next, carrying out high-temperature activation through CO<2> or vapor. The prepared porous carbon nanofiber electrode, with obviously enlarged specific surface area and improved oxygen-containing functional group, has high electrocatalytic activity and electrochemical reversibility when the porous carbon nanofiber electrode is used for the redox flow battery; the redox flow battery has the advantages of simple preparation method, easily available raw material, low cost and the like; the electrode material is applicable to the redox flow battery; due to the ultra-thin electrode thickness, space between electrodes of the battery can be reduced, and internal resistance of the battery can be lowered; and in addition, charge transfer resistance can be lowered, the voltage efficiency and energy efficiency of the all-vanadium redox flow battery are improved, and the weight and the volume of the battery are reduced.

The invention discloses a carbon nanofiber / metal composite electrode for a flow battery and a preparation method thereof. The electrode material is prepared by the following steps of: taking a mixtureof a high-molecular polymer and a metal salt as a precursor; preparing nanofibers by adopting an electrostatic spinning method; and performing high-temperature carbonization treatment, and performingsurface oxidation and etching to manufacture the electrode material, wherein the diameter of the carbon nanofibers is 100-1000 nm, the diameter of the metal particles is 2-100 nm, the metal particlesare distributed on the surfaces of the carbon nanofibers, one parts of the metal particles are embedded into the carbon nanofibers, and the other parts of the metal particles are exposed out of the surfaces of the carbon nanofibers. The carbon nanofiber / metal composite electrode prepared by adopting the preparation method has good electrocatalytic activity and electrochemical reversibility when used for the flow battery, and has the advantages of simple preparation method, few procedures, easily available raw materials, low price and the like.

The invention discloses a liquid crystal electrolyte solution for a dye-sensitized nano film solar battery, which is formed from components 1 and 2 or components 1, 2 and 6 as main components by compounding or not compounding one or several components in other four components, wherein the component 1 is liquid crystal electrolyte; the component 2 is an oxidation-reduction pair with good electrochemical reversibility; the component 3 is a dark current inhibitor; the component 4 is a hetero-atom containing compound acting with positive ions in the electrolyte solution; the component 5 is a hetero-atom containing compound acting with I2 in the electrolyte solution; the component 6 is an organic solvent or an ionic liquid; and the component 7 is a compound for improving the ultraviolet performance of the battery. The liquid crystal electrolyte solution has the advantages of higher electrical conductivity, good electrochemical reversibility, good low-temperature stability, stronger ultraviolet resistance, efficiency improvement of the solar battery, life prolonging of the solar battery, stable performance, no environmental pollution and the like.

The invention discloses an oxygen-containing functional group gradient distribution reduced graphene oxide / graphene foam composite and an application thereof to vanadium redox batteries, belonging to the field of battery materials and energy storage. Graphene foam is obtained by a chemical vapor deposition method, a three-dimensional graphene foam and graphene oxide aerogel structure is obtained in combination with graphene oxide aerogel preparation and metals are utilized for gradient reduction, thus achieving integration of high conductivity of a thee-dimensional network of graphene and graphene oxide with abundant oxygen-containing functional groups. The composite has the advantages and beneficial effects that by using the material as the electrode material of the vanadium redox batteries, the electrocatalytic activity and electrochemical reversibility of the V<2+> / V<3+> and VO<2+> / VO2<+> oxidation reaction can be improved, the charge transfer resistance can be reduced, the energy efficiency of the vanadium redox batteries can be improved and the cycle lives of the vanadium redox batteries can be prolonged; the composite has the characteristics of simplicity and convenience in operation, high yield and easiness in structure adjustment and control and has a terrific application prospect.

The invention discloses a dehydrogenase electrode, and a preparation method and application thereof. The dehydrogenase electrode comprises a substrate electrode, a catalyst layer coated on the substrate electrode, and a dehydrogenase layer coated on the catalyst layer, wherein the catalyst layer is the compound of polyaniline and carbon nano material; and the dehydrogenase layer comprises (a) dehydrogenase or (b) dehydrogenase cross-linked by cross-linking agent. The dehydrogenase electrode can be used as an electrode of a biological fuel cell, and has high electrochemical reversibility in neutral solution; and meanwhile, in buffer solution (pH value is 7) with NAD+ (nicotinamide adenine dinucleotide, oxidation), different dehydrogenases can be used for respectively realizing selective electrochemical sensing of glucose, ethanol, lactic acid and the like.

The invention discloses a nitrogen-doped carbon composite SnFe2O4 lithium ion battery negative electrode material as well as a preparation method and an application thereof; the preparation method ofthe lithium ion battery negative electrode material comprises the following steps of 1) performing co-deposition on an iron source and a tin source under the effect of a surfactant Tween-20 to generate SnFe2O4 nanoparticles; 2) enabling the SnFe2O4 nanoparticles and dopamine hydrochloride to be reacted in a Tris-HCl buffer solution to prepare a precursor; and 3) performing calcining on the precursor in an inert atmosphere. The negative electrode material of the lithium ion battery disclosed by the invention is the nitrogen-doped carbon composite SnFe2O4 nanoparticles, and has the advantages ofbeing stable in structure, high in charge-discharge efficiency, excellent in cycle performance, high in electrochemical reversibility and the like; and the negative electrode material is simple in preparation process, low in cost and environment-friendly, is suitable for practical application of the lithium ion battery, and can realize industrial large-scale production.

The invention provides a modification method for a carbon felt electrode for all-vanadium redox flow batteries. A carbon felt is immersed in absolute ethyl alcohol or acetone, ultrasonically treated,then washed clean with pure water and dried for later use; the dried carbon felt is put into a closed container and suspended over concentrated nitric acid solution in the closed container; the closedcontainer is heated, and high-temperature and high-pressure nitric acid vapor produced in the container is utilized to carry out gas-phase oxidation treatment on the carbon felt; after the carbon felt is cooled, absolute ethyl alcohol and pure water are respectively used for washing the carbon felt clean, and after drying, a modified carbon felt is obtained. The method is simple and practical, the electrocatalytic activity and stability of the carbon felt electrode are greatly increased, the surface oxidation of the carbon felt is more uniform and the oxidation degree can be accurately controlled by regulating the dosage of nitric acid, heating temperature and treatment time, in addition, a great deal of cost is reduced because the dosage of nitric acid is little and the problem of wastealmost does not exist, and therefore the modification method can be easily applied in practical production.

The invention relates to a novel battery which adopts vanadic sulfate as active material for an anode and a cathode of the battery. The active material for the anode is paste solid material of mixture of sulfates with 5 valence vanadium and 4 valence vanadium respectively (among which the content of sulfates with 5 valence vanadium and 4 valence vanadium is 50 percent respectively. ), sulfate, lithium sulfate, graphite powder, polyviny1 alcohol and water mixed evenly by the proportion of 40 to 80 per cent: 1 to 10 per cent:1 to 10 per cent:5 to 20 per cent:1 to 5 per cent:5 to 15 per cent and filled solidly. The active material for the cathode is the paste solid material of mixture of sulfates with 3 valence vanadium and 2 valence vanadium respectively (among which the content of sulfates with 3 valence vanadium and 2 valence vanadium is 50 per cent respectively), sulfate, lithium sulfate, graphite powder, polyviny1 alcohol and water mixed evenly in the proportion of 40 to 80 per cent: 1 to 10 per cent:1 to 10 per cent:5 to 20 per cent:1 to 5 per cent:5 to 5 per cent and filled solidly. The battery provided by the invention is a rechargeable vanadium battery of dry type. The invention is characterized by good electrochemical reversibility and long cycle life due to adopting vanadium element of ionic status as the active material. The vanadic sulfate of the active material is made into paste solid, thus presenting the advantages of a dry battery.

The invention discloses an ammonia desulphurization and denitrification process for flue gas by synchronization of complexing absorption and electrolytic regeneration and solves the problem of low absorption liquid regeneration efficiency in an existing synchronous ammonia desulphurization and denitrification process for the flue gas. The technical scheme includes that the flue gas is pressurized and then fed into a concentration tower to realize contact reaction with concentration liquid in the tower, the flue gas discharged from the concentration tower is fed into an absorption tower to realize contact reaction with cyclic absorption liquid in the absorption tower, the concentration liquid at the bottom of the concentration tower is subjected to deferrization through a first electrolytic reactor after reaction and then fed into an ammonium sulfate crystallization system, the absorption liquid at the bottom of the absorption tower is regenerated and then fed back to the upper portion of the absorption tower to serve as the cyclic absorption liquid, the concentration liquid enters an anode chamber of a reaction unit of the first electrolytic reactor to realize oxidation reaction and then enters a cathode chamber to realize a reduction reaction, and an electrolytic solution is discharged through a short outlet connection pipe of the reactor after reaction and fed into the ammonium sulfate crystallization system. The ammonia desulphurization and denitrification process for the flue gas by synchronization of complexing absorption and electrolytic regeneration has the advantages of simplicity, low investment cost and operation cost, high conversion efficiency and effectiveness in deferrization, desulphurization and denitrification.

The invention discloses a sandwich-shaped hollow spherical lithium ion battery anode material and a preparation method thereof. A reduced graphene oxide hollow sphere is used as a matrix, tungsten chloride and thioacetamide are used as raw materials, and under a hydrothermal condition, a tungsten disulfide nanosheet can be grown on the surface of the hollow sphere vertically in situ. The entire electrode material is coated with a third layer shell by a reflow soldering method. Finally, a NG@WS2@Hs-rGO type sandwich anode material is prepared by nitrogen doping in a heat treatment process, so as to improve the disadvantage of volume expansion of the tungsten disulfide. The method has a simple principle and a mild condition and can prepare alithium ion battery anode material with excellent electrochemical performance.

The invention relates to a positive pole piece of a lithium-sulfur battery based on an L-cysteine or L-cystine agent as an additive and a preparation method thereof. According to the method, based on gelatin as a binder, the L-cysteine or L-cystine additive is introduced, thus the redox property of a sulphur electrode is obviously improved, and the electrochemistry reversibility and circulation stability of the lithium-sulfur battery are significantly improved.

An electrochromic medium comprises a cathode electrochromic compound, wherein the structural formula of the cathode electrochromic compound is as shown in the specification, R1 is selected from normal alkyl or heterogeneous alkyl containing 1-20 carbon atoms; each of R2-R14 is independently selected from H, alkyl, cycloalkyl, polycyclic alkyl, aryl, heterocyclic alkyl, aromatic alkyl and alkaryl containing 1-50 carbon atoms or alkyl, cycloalkyl, polycyclic alkyl, aryl, heterocyclic alkyl, aromatic alkyl and alkaryl containing 1-50 carbon atoms and halogen, N, O, S, Si, P or unsaturated bond groups; X1<-> is selected from acetate anion, methyl phenyl acetate sulfonate anion, tetrafluoroborate anion, hexafluoroborate anion, tetraphenyl borate anion, trifluoro mesylate anion, perchlorate anion, bis-oxalate borate anion, oxalate difluoroborate anion, bis(trifluoromesyl) imide anion and tri(trifluoromesyl) methyl anion. The cathode electrochromic compound has the advantages that good electrochemical reversibility is achieved, fast color changing and good stability are achieved, the lowest value of visible light transmittance is small, and the like.

The invention discloses a carbon-containing material light-weight grid for a lead-acid storage battery and a preparation method of the carbon-containing material light-weight grid. Ribs of the carbon-containing material light-weight grid are of strip-shaped structures and comprise carbon-containing materials. The ribs are of a strip-shaped sheath-core structure or a strip-shaped tubular structure.The preparation method comprises: coating a core layer with a skin layer, and obtaining the carbon-containing composite conductive material in a cold extrusion coating mode, comprising the followingsteps: (1) a rod blank of the carbon-containing material entering an extrusion wheel groove, the rod blank being subjected to extrusion forming through a die orifice to form a tubular structure, and obtaining a skin layer of a tubular rib or a strip-shaped skin-core structure rib; (2) coating the core layer material with the tubular skin layer to obtain a rib material capable of being used for preparing the grid; and (3) preparing the grid of the lead-acid storage battery from the rib material. The grid has the advantages of strong conductivity, high strength, excellent corrosion resistance, excellent electrochemical reversibility, strong electrochemical activity and the like, the quality of the grid is greatly reduced compared with the prior art, and meanwhile, the preparation method is simple and controllable to operate.

The invention discloses an ultralow-temperature lithium-ion battery and a preparation method thereof. In view of improving the dispersion capability of lithium ions in an active material and electrodeinterface performance, electrochemical reversible performance and low-temperature conducting performance of the lithium ions are effectively improved through optimizing material performance and improving a pulping technology, and the electrode specific capacity is improved. According to the preparation method disclosed by the invention, the prepared lithium-ion battery has 0.2C discharge under anultralow-temperature environment condition of -60 DEG C, the capacity retention rate still can reach 80 percent or more, and the lithium-ion battery can be normally charged at the temperature of -60DEG C; the technical difficulty that a traditional lithium-ion battery are difficult to use normally at the low-temperature that the temperature is lower than -20 DEG C is broken through; an application range of the lithium-ion battery on military equipment is greatly expanded.

The invention belongs to the field of renewable energy sources, and particularly relates to an aqueous full-organic flow battery based on indigo derivatives and a construction method and application thereof. According to the battery, a water-soluble indigo reduced derivative is taken as a negative electrode electroactivity species, a water-soluble indigo oxidized derivative is taken as a positiveelectrode electroactivity species, sulfuric acid is taken as a supporting electrolyte, and a perfluorosulfonic acid-polytetrafluoroethylene copolymer membrane is taken as an ion exchange membrane. Thebattery prepared in the invention, which is an aqueous flow battery with good electrochemical performance, has the advantage that the active electrolyte is adjustable in structure, simple in manufacturing, long in cycle life and high in specific power, the used aqueous electrolyte is low in cost, safe and environmentally-friendly, and the battery has wide application prospects in the fields of large-scale electricity storage of wind energy and photovoltaic power generation and peak regulation of power network.

The invention provides a preparation method of a mesoporous hollow carbon micron cage supercapacitor electrode material. The preparation method comprises the following steps: by taking Fe2O3 as a hardtemplate, F127 as a soft template and dopamine hydrochloride as a carbon source, stirring and polymerizing at normal temperature, centrifuging, washing and drying the obtained product, and calciningand carbonizing for 1-4 hours at 500-900 DEG C in an inert atmosphere to obtain the mesoporous hollow carbon micron cage material. According to the method, the mesoporous hollow carbon micron cage hasrich mesoporous structures and hollow structures, an effective channel is provided for ion transmission and diffusion, and rapid electrochemical response can be ensured. The material shows good supercapacitor performance as an electrode material.

The invention discloses a mesoporous tricobalt tetroxide nanorod, a preparation method thereof, a supercapacitor electrode material and an electrode. The preparation method includes: a, preparing rodlike mesoporous silicon dioxide; b, mixing the rodlike mesoporous silicon dioxide with a cobalt salt solution, and removing solvent to obtain a cobalt salt-rodlike mesoporous silicon dioxide load; c, subjecting the cobalt salt-rodlike mesoporous silicon dioxide load to decomposing reaction to obtain a tricobalt tetroixde-rodlike mesoporous silicon dioxide compound; d, subjecting the tricobalt tetroixde-rodlike mesoporous silicon dioxide compound and alkali liquid to double-decomposing reaction to obtain the mesoporous tricobalt tetroxide nanorod. The supercapacitor electrode made by the mesoporous tricobalt tetroxide nanorod has the advantages of excellent electrochemical reversibility, high specific capacitance, low charge transfer resistance, low charge transfer internal resistance and stable cyclicity.

The invention discloses a multifunctional negative material. A carbon material is taken as a matrix; the surface of the material is modified by an electrocatalyst containing Pb; the electrocatalyst containing the Pb is one / two or more of a Pb simple substance, PbO<2> or lead sulfate; and the deposit rate of the electrocatalyst containing the Pb on the matrix is 0.05wt% to 80wt% of that of the multifunctional negative material. The electrode is applicable to a negative electrode of an all-vanadium redox flow battery; the electrocatalytic activity and the electrochemical reversibility of the electrode material on a V<2+> / V<3+> redox reaction can be improved; the charge transfer resistance is reduced; the multifunctional negative material has high hydrogen evolution over-potential; a hydrogen evolution reaction can be inhibited; the service lifetime of the battery is prolonged; and the charge and discharge capacity of the battery can also be improved. According to the multifunctional negative material, the voltage efficiency and the energy efficiency of the all-vanadium redox flow battery are improved, so that the working current density of the all-vanadium redox flow battery is improved; and the weight, the size and the cost of the battery with the same output power are greatly reduced.

The invention discloses a lithium-yttrium co-doped high-performance sodium ion battery positive electrode material and a preparation method thereof. The sodium ion battery positive electrode material is a lithium-yttrium co-doped P2 type layered transition metal oxide material, the specific chemical formula is NaxFeaMnbLicYdO2, wherein 0.6 < = x < = 0.7, 0 < a < = 0.27, 0.62 < = b < = 0.75, 0.11 < = c < = 0.175, and 0 < d < = 0.1. The preparation process comprises the following steps: preparing a precursor by using a wet ball milling method, and then calcining step by step by using a medium-low temperature solid phase sintering method to synthesize a target material, wherein the first reversible capacity of the material is about 200-220mAh / g. The prepared material can be applied to the field of sodium ion batteries, oxygen ions in the material can participate in a redox reaction, and rare earth Y < 3 + > ions have a strut effect, so that the material has the advantages of high working voltage, high energy density and good structural stability; and the prepared material is rich in element reserves related to synthesis, environment-friendly, low in manufacturing cost and wide in application prospect.

The invention relates to an ampere humidity sensor and a relative check method, based on room temperature ion liquid, which comprises a humidity sensitive element with room temperature ion liquid and electrochemical probe, a signal amplifier circuit, a check circuit, a reference circuit, a gas system, and a display control system, to use the charge current of the humidity sensitive element and the reaction current of the electrochemical probe to detect the humidity. The invention is characterized in that using the room temperature ion liquid as the sensitive part of humidity, using the change of reversal electrochemical property of oxidization reduction couple to detect the humidity of current type. The invention can overcome the defects of prior humidity sensor as bad exchangeable property, high cost, complex device, bad interference resistance, and small response signal linear range, caused by using alternative-current signal, to obtain the advantages as simple structure, low cost, stable property and high sensitivity.

The invention provides an electrolyte used for vanadium cells and a preparation method of the electrolyte. The electrolyte is made by adding methanesulfonic acid into an electrolyte containing quadrivalent and trivalent vanadium ions and obtained through electrolysis. The provided electrolyte is obviously improved in the electrode reaction activity and charge-discharge energy efficiency of vanadium cells.

The invention discloses an alkaline secondary battery and a preparation method thereof, and belongs to the technical field of alkaline secondary batteries. The alkaline secondary battery comprises a diaphragm, an alkaline aqueous solution electrolyte, a positive electrode and a negative electrode, an active matter of the positive electrode is a Co-Ni-B compound, and an active matter of the negative electrode is a boride. The invention also comprises a preparation method of the alkaline secondary battery, which comprises the following steps: assembling the positive electrode, the diaphragm and the negative electrode in sequence, and adding the alkaline aqueous solution electrolyte to obtain the alkaline secondary battery, wherein the boride in the negative electrode is prepared by the following steps: dissolving hydroboron in an alkaline aqueous solution with the pH value of 10-14, and then dropwise adding the alkaline aqueous solution into a metal salt solution to obtain the boride. The alkaline secondary battery still has outstanding electrochemical performance at low temperature.

The invention belongs to the field of chemical analysis and detection, provides a three-dimensional porous carbon / polythionine compound modified electrode and a production method thereof, and also provides an electrochemical detection method based on the electrode. The three-dimensional porous carbon / polythionine compound modified electrode includes a base electrode, a polythionine coating and a three-dimensional porous carbon coating, the external surface of the base electrode is wrapped with the polythionine coating, and the external surface of the polythionine coating is wrapped with the three-dimensional porous carbon coating to form the three-dimensional porous carbon / polysulfide composite modified electrode. The three-dimensional porous carbon / polythionine compound modified electrodehas good electron transfer ability and can improve the reaction rate of the electrode, the production method has the advantages of simplicity, easiness in implementation, and low cost, and the electrochemical detection method based on the electrode has the advantages of simplicity in operation, good selectivity and high sensitivity.