376 results about "Charge separation" patented technology

The invention discloses a novel photocatalyst for producing hydrogen from organic matter wastewater and a preparation method of the novel photocatalyst, and relates to the technical field of photocatalysis. The photocatalyst disclosed by the invention is combined with oxidation-reduction capability, and can effectively degrade and produce hydrogen under the irradiation of sunlight. Through combination of quaternized porous tungsten oxide and vanadate radicals, silver vanadate load growth is promoted, the sunlight utilization rate is increased, and the electron-hole recombination rate is reduced. Reduced graphene oxide is used for pretreatment, active groups are introduced, the reduced graphene oxide is compounded with tungsten oxide / silver vanadate, the binding force is enhanced through heat treatment, photo-induced electron-hole pair compounding is inhibited through the conductivity, and the visible light catalytic performance is improved. The adsorption effect of porous tungsten trioxide and reduced graphene oxide can accelerate the degradation of organic matters. By optimizing the proportion of silver vanadate, tungsten oxide and reduced graphene oxide, the visible light response and charge separation efficiency are enhanced, the degradation and hydrogen production performance is improved, and light corrosion is reduced.

The invention relates to the technical field of composite catalyst materials, in particular to a ferrocobalt bimetal hydroxide / BCN composite material and a preparation method and application thereof.The preparation method comprises the steps that cobalt nitrate and ferric nitrate are used for preparing a metal salt solution, sodium carbonate and sodium hydroxide are used for preparing a precipitant solution, a B-doped carbon nitride BCN material is added into the metal salt solution to form a uniform suspension, and the suspension is dried to obtain the ferrocobalt bimetal hydroxide / BCN composite material; dropwise adding the precipitant solution into the suspension to obtain a precursor solution, performing hydrothermal reaction on the precursor solution, and performing centrifugal impurity removal and drying to construct a heterostructure between layered double hydroxide and BCN in situ to obtain the Co-Fe LDH-coated BCN composite material. Through boron doping and heterostructure construction, the charge separation capacity of graphite carbon nitride is enhanced, the electron migration efficiency is improved through a heterointerface structure, the metal ion release amount and the cycle stability are controlled, and the catalytic performance is remarkably improved.

The invention provides a Cu2O-based heterogeneous composite material as well as a preparation method and application thereof. The preparation method comprises the following steps: coating the surface of a Cu2O hollow sphere substrate with a carbon layer, and depositing layered double hydroxides (LDHs) and metal palladium (Pd) nanoparticles on the carbon layer. According to the material, through a Cu2O-carbon layer-LDHs-Pd multistage heterostructure design, space optimization of light absorption, charge transfer and catalytic sites is realized; cu2O-carbon layer-LDHs interface coupling promotes directed migration of photo-induced electron-hole pairs, and the surface plasmon resonance effect of Pd nanoparticles enhances the charge separation efficiency; the LDHs optimizes a charge transfer path through surface oxygen vacancy or metal valence cycle, so that synergistic oxidation of non-free radicals and free radicals is realized, the organic matter degradation efficiency is remarkably improved, the oxidation path is widened, and the performance bottleneck of a single material is broken through.

The invention belongs to the technical field of immunoassay and biosensing, and provides a novel construction mode of a heterojunction dual-photoelectrode photoelectric sensing strategy and a preparation method of an in-situ heterojunction MIO photocathode. The invention relates to a preparation method of a heterojunction dual-photoelectrode type photoelectrochemical sensor based on multi-ball cascade DNA reaction amplification. Specifically, the design is composed of an In2O3 / CdS photoanode and an in-situ formed MIL-68 / In2O3 (MIO) photocathode. The heterojunction dual-photoelectrode sensing strategy effectively prolongs an electron-hole transmission path, enhances photo-generated charge separation, and realizes' super-open 'PEC signal output, thereby providing a steady baseline for signal conversion. Meanwhile, a multi-sphere cascade DNA reaction is combined to output a three-dimensional DNA net structure to provide a large number of sites for embedding of a PEC quenching probe doxorubicin-ferrocene carboxylic acid (DOX-FcCOOH), obvious PEC signal quenching is realized by utilizing the efficient competitive electron transfer capability of the three-dimensional DNA net structure, and finally, a signal conversion system with'opening-super opening-closing 'multistage response characteristics is constructed. The detection of the nucleic acid marker Pax-5a gene of the B cell acute lymphatic leukemia is realized by detecting target objects with different concentrations.

The invention is suitable for the technical field of photocatalyst preparation, and provides a modified tubular g-C3N4 loaded Ni-CoP photocatalyst and a preparation method thereof. The preparation method comprises the following steps: calcining a carbon nitride precursor in stages to obtain tubular carbon nitride, stirring the tubular carbon nitride with a cobalt and nickel-containing compound and an alkaline compound, washing and drying to obtain a precipitate, calcining, mixing and grinding with a phosphorus-containing compound, calcining again, and modifying the product with polydopamine and polypyrrole to obtain the composite material. The photocatalyst modified by the polydopamine and the polypyrrole and loaded with the Ni-CoP by taking the tubular g-C3N4 as the carrier is obtained. According to the invention, three-in-one synergistic integration of'carrier-modifier-cocatalyst 'is realized, the prepared photocatalyst still keeps tubular morphology and has a larger specific surface area, the requirements of anode oxygen evolution reaction (OER) on rapid charge separation and transmission can be met, meanwhile, the light absorption range is widened, the solar energy utilization rate is increased, and a foundation is laid for efficient OER reaction.

The invention discloses a current collector composite copper foil film spreading method and device, and the method comprises the steps: applying a DC electric field to a current collector composite copper foil, forming an interface charge separation layer, obtaining reference capacitance distribution data, applying a film spreading tension to enable the material layers to generate microscopic displacement, and obtaining capacitance change data. The method comprises the following steps: analyzing and identifying an abnormal adhesion area through time domain difference and sliding window correlation, applying periodic micro-stress disturbance to the abnormal area to establish a stress-capacitance response relation to invert adhesion strength spatial distribution, and periodically recording a capacitance reference value to evaluate the interface adhesion fatigue degree. The device comprises an electric field processing module, a film spreading tension module, a correlation analysis module, a stress disturbance module and a fatigue evaluation module. According to the scheme, real-time dynamic detection and quantitative evaluation of the interlayer adhesion strength in the current collector composite copper foil film spreading process can be realized, the interface adhesion failure and fatigue accumulation state can be effectively identified, and accurate technical support is provided for battery current collector preparation process optimization and product quality control.

The invention relates to the technical field of electroluminescence, and discloses a laminated organic light-emitting device and application thereof, and the laminated organic light-emitting device comprises an anode layer, a first light-emitting unit, an electron transport layer, an interface modification layer, a connection layer, a second light-emitting unit and a cathode layer which are sequentially arranged from bottom to top; the electron transport layer comprises a hole blocking layer and an n-type electron transport layer; wherein the n-type electron transport layer is composed of an n-type dopant and an organic electron transport material, has the functions of electron transport, charge separation and injection and regulation and control of the optical microcavity effect of the laminated device, can simplify the electron transport and connection layer structure of the laminated device, and effectively improves the conductivity of the laminated device; according to the laminated organic light-emitting device, the voltage drop of the body is obviously reduced, and the interface electron injection barrier is reduced, so that the laminated organic light-emitting device has the advantages of low driving voltage, high efficiency and long service life, and the effect of adjusting the optical microcavity of the device can be achieved by utilizing the n-type electron transport layer.

The invention provides a double-defect-modified porous carbon nitride photocatalyst prepared by one step from ferromolybdic acid as well as a preparation method and application of the double-defect-modified porous carbon nitride photocatalyst. The catalyst is of a thin-layer porous structure, so that the specific surface area of the catalyst is increased, and more surface active sites are provided for adsorption and reaction; compared with pure g-C3N4, the visible light absorption intensity of the catalyst is obviously enhanced, due to the existence of surface N vacancies and defects formed by doping of metal oxides, effective charge separation is enhanced, the photon-generated carrier separation and transfer capacity is higher under visible light irradiation, and the catalytic activity is remarkably improved. When the photocatalyst is applied to degradation of tetracycline antibiotic pollutants, photocatalytic degradation of tetracycline can be realized only under the condition of low-power 5W LED visible light, the preparation process is simple, and the cost is lower.

The invention relates to preparation of a crystalline allyl covalent organic framework material and application research of the crystalline allyl covalent organic framework material in benzamide cyclization green photocatalytic conversion. The SF-COF material is prepared by adopting a step-by-step synthesis method. The preparation method comprises the following steps: synthesizing a COF precursor by taking 1, 3-benzenetricarboxaldehyde and p-aminophenylacetonitrile as raw materials, and preparing the allylation covalent organic framework material with the electronic push-pull effect from the COF precursor and 5, 5 ', 5'-(benzene-1, 3, 5-triyl) tri (thiophene-2-formaldehyde) through a solvothermal method. The material is applied to the field of photocatalytic organic conversion, and benzamide cyclization and conversion of derivatives of benzamide are achieved under irradiation of a blue light LED. The prepared SF-COF has the advantages of efficient charge separation and electron conduction performance, good structural stability and chemical stability and the like. And a catalyzed organic reaction substrate has the advantages of wide universality range, good cycle stability and the like, and shows excellent photocatalytic conversion capability.

The application discloses a preparation method and application of a ferroelectric full water-splitting photocatalyst. The preparation method comprises the following steps: S1: pretreating a ferroelectric material to obtain a pretreated ferroelectric material; S2: after atomic layer deposition of the pretreated ferroelectric material and a metal organic complex source material, non-active gas I is introduced to perform blowing I, water is introduced, non-active gas II is introduced again to perform blowing II, and the first deposition is completed; and S3: according to the thickness of the ferroelectric full water-splitting photocatalyst, the step S2 is circularly performed to obtain the ferroelectric full water-splitting photocatalyst. The ferroelectric material can efficiently photocatalyze full water splitting through accurate regulation and modification of the surface of the ferroelectric material by the atomic layer deposition technology. The method not only provides an experimental basis for researching the limiting factors of the ferroelectric material in a photocatalytic reaction, but also provides a new idea for constructing an efficient photocatalyst by using efficient charge separation and depolarization electric field of the ferroelectric material.

The present disclosure relates to the technical field of display, and provides a light-emitting device and a display panel. The light-emitting device comprises a first electrode, a second electrode, a plurality of light-emitting units arranged between the first electrode and the second electrode, and a charge separating generating unit arranged between adjacent light-emitting units, wherein a light-emitting center of the light-emitting unit is located at an antinode point of a resonance wave of a resonant microcavity formed between the first electrode and the second electrode.

The invention relates to a high-performance positively charged composite membrane and a preparation method thereof, in particular to a nanofiltration membrane containing a sulfonated imino covalent organic framework (TpPa-SO3H) interlayer. The nanofiltration membrane adopts a three-layer structure design, and comprises a base membrane layer, a TpPa-SO3H middle interlayer and a positively charged separation surface layer. Wherein the TpPa-SO3H interlayer is formed by in-situ growth of polyphenol and sulfated amine under the action of an oxidizing agent, and the separation surface layer is assembled and constructed through electrostatic attraction and hydrogen-bond interaction between positively charged polyelectrolyte and sulfonic acid groups. The TpPa-SO3H interlayer is introduced to effectively regulate and control the pore size distribution and hydrophilicity of the surface of the substrate, the formed negative electricity interlayer can promote the assembly of a polyelectrolyte positive electricity layer, and the interception performance and the operation stability of the composite membrane on heavy metal cations are remarkably improved. Compared with a traditional nanofiltration membrane, the composite membrane prepared through the method keeps high water flux (larger than or equal to 40 L.m <-2 >. H <-1 >. Bar <-1 >), meanwhile, the rejection rate of heavy metal cations such as Cr < 3 + >, Mn < 2 + > and Co < 2 + > is larger than or equal to 95%, and the composite membrane has excellent long-term operation stability. The preparation method is simple in process and low in cost, and has a wide application prospect in the field of heavy metal wastewater treatment.

The invention discloses a UiO-66 (Ce) / ZnO composite photocatalyst as well as a preparation method and application thereof, and relates to the technical field of photocatalytic degradation of water pollution. The method specifically comprises the following steps: preparing zinc oxide by taking zinc acetate dihydrate, absolute ethyl alcohol and sodium hydroxide as raw materials; and dispersing the obtained zinc oxide in a DMF solution containing terephthalic acid, adding a ceric ammonium nitrate aqueous solution, and carrying out a heating reaction to synthesize the UiO-66 (Ce) / ZnO composite photocatalyst. According to the invention, ZnO and UiO-66 (Ce) are used for constructing a heterojunction for the first time, and the design not only widens the visible light response range, but also significantly improves the charge separation efficiency, thereby greatly enhancing the photocatalytic performance. The preparation process is simple and convenient, and the conditions are environment-friendly. The degradation rate of the obtained composite photocatalyst on tetracycline in waste water under visible light can reach 91.2%, the composite photocatalyst has good recoverability and reusability, a new scheme is provided for efficient degradation of organic pollutants, and the composite photocatalyst has remarkable advantages in the field of environmental protection.

The invention relates to the technical field of photocatalysis, in particular to a copper and titanium co-doped potassium niobate photocatalytic material and a preparation method thereof. Potassium niobate is partially substituted in the synthesis stage of potassium niobate through a hydrothermal method, the crystal structure of potassium niobate can be kept stable after doping, the light absorption range is widened, and the photocatalytic efficiency is improved. Other potassium niobate doped photocatalytic materials are difficult to consider both the performance and the practicability due to the problems of structural defects, charge imbalance, insufficient light absorption or poor stability and the like. Cu-Ti co-doping achieves breakthrough in the aspects of band gap regulation and control, charge separation and structural stability through a complementary mechanism, the peak value of transient photocurrent response and steady-state output are remarkably improved, and the optimal solution of potassium niobate modification is achieved.

The invention discloses a triarylmethane type I photosensitive dye as well as a synthesis method and application thereof. The structure of the dye is shown as a general formula I; intramolecular charge separation is optimized by regulating substituent groups, and the generation efficiency of superoxide anions and hydroxyl radicals is remarkably improved. According to the synthesis method, 4-diphenylaminobenzaldehyde or 4-vinyl benzaldehyde is used as a raw material, efficient preparation is achieved through the steps of condensation, oxidation and the like, the raw material is easy to obtain, and operation is easy and convenient. The dye has strong absorption at the wavelength of 600-630 nm, is suitable for red light triggered photodynamic therapy (PDT), especially keeps high reactive oxygen yield under the hypoxic condition, and breaks through the oxygen dependence limitation of traditional PDT. Experiments show that the dye can induce ferroptosis of tumor cells, has the functions of fluorescence imaging and treatment, and has wide application prospects in the fields of antitumor drugs, in-vivo fluorescence labeling, photoresponsive functional preparations and the like.

The invention belongs to the technical field of reverse osmosis membranes, and relates to a visible-light-responsive carbon nitride / zinc oxide heterojunction modified reverse osmosis membrane and a preparation method thereof.The method specifically comprises the steps that porous ultrathin carbon nitride nanosheets are prepared; synthesizing zinc oxide nanoparticles rich in oxygen vacancies; and compounding the two to form the Z-type heterojunction photocatalyst. The heterojunction is stably loaded in a polyamide separation layer through an interfacial polymerization process, the composite reverse osmosis membrane is prepared, and the membrane disclosed by the invention has a remarkable visible light response characteristic while maintaining a high desalination rate. The method has the core advantages that the visible light utilization rate and the photo-generated charge separation efficiency are remarkably improved through the construction of the heterojunction, so that the membrane can actively and efficiently degrade organic pollutants under illumination, self-cleaning is realized, the anti-pollution capacity is greatly improved, and the chemical cleaning period is greatly prolonged.

The invention relates to the technical field of photocatalytic materials, in particular to a multi-ion doped TiO2 nanosheet material suitable for degradation of dyes in water and a preparation method of the multi-ion doped TiO2 nanosheet material. The preparation method comprises the following steps: pre-embedding a self-sacrifice template in a germanium-tungsten composite doping solution, carrying out hydrothermal conversion to construct a Ge-W synergetic optimized regular TiO2 substrate, carrying out atomic layer deposition to realize nitrogen / silver uniform doping, and carrying out synergetic surface modification on silver nitrate-ethanolamine and perfluorosilane to prepare the TiO2 nanosheet material. Germanate serves as lattice strain guidance to guide TiO2 lattice growth to form a low-defect matrix, tungstate is cooperatively doped in the matrix to construct a strong built-in electric field to improve the charge separation efficiency, Ge-W elements cooperate to stabilize a bulk phase and a grain boundary, and a gradient protection barrier is constructed with selective shielding of a fluorosilane layer. The TiO2 catalyst is synergistically improved in the aspects of high catalytic activity and long-acting environmental stability, and is suitable for efficient pollutant purification in a complex water quality environment.

The invention relates to a photocatalytic fuel cell based on a cadmium sulfide titanium dioxide composite photo-anode and application, and relates to the technical field of preparation of novel photo-electrode materials, the cell adopts a continuous ion deposition method to prepare a CdS quantum dot modified TiO2 photo-anode with a specific layer number, and the CdS quantum dot modified TiO2 photo-anode, a platinum cathode and an ion exchange membrane form a synergistic system. The layer number and the particle size of CdS quantum dots in the photo-anode are accurately controlled, an efficient heterojunction structure is constructed, and the visible light utilization and charge separation efficiency is improved to the maximum extent; a chemical bonding effect is formed on the surface of the photo-anode by using carboxyl-containing organic fuel, so that an electron transmission path is obviously accelerated; the dual functions of organic wastewater degradation and electric energy synchronous output are achieved, and long-term operation stability is kept. The technology provides an efficient and low-consumption solution for resourceful treatment of industrial organic wastewater.

The application discloses a kind of efficient silicon-based water-voltage devices and preparation method thereof, the silicon-based water-voltage device is composed of positive electrode, hole selective transport layer, silicon nanostructure, silicon substrate and negative electrode from top to bottom, the top end part of the silicon nanostructure is embedded in the hole selective transport layer.This application introduces hole selective transport layer in the interface of silicon nanostructure / positive electrode, uses the internal electric field formed by high work function hole selective transport layer in interface to prevent the migration of electron to positive electrode, realizes the selective transport of hole, reduces interface recombination loss to improve charge separation and collection efficiency;At the same time, the hole selective transport layer introduced realizes the transition of silicon nanostructure and positive electrode from point contact to surface contact, reduces the contact resistance of positive electrode interface, further promotes the efficient transport of hole at interface, thereby increases the collection efficiency of electrode to hole, under the synergistic effect of the above, effectively improve the electrical properties of silicon-based water-voltage device.

The application provides a one-dimensional iron oxide nanorod heterojunction composite material and a preparation method and application thereof, and belongs to the technical field of photoelectrocatalytic water splitting hydrogen production. The composite material provided by the application comprises: one-dimensional iron oxide nanorods, cuprous sulfide nanoparticles loaded on the one-dimensional iron oxide nanorods, and cobalt hydroxide nanosheets coated on the surfaces of the one-dimensional iron oxide nanorods and the cuprous sulfide nanoparticles. On one hand, the Fe2O3 / Cu2S p-n heterojunction is introduced to accelerate the separation of photo-generated carriers in the Fe2O3 nanorod array, and on the other hand, the Co(OH) x The surface OECs accelerate the kinetics process of interfacial water oxidation, the rapid depletion of photo-generated holes further improves the charge separation of the photoanode surface, and the synergistic effect between the Fe2O3 / Cu2S p-n heterojunction and the OECs significantly improves the PEC water splitting performance of the iron oxide nanorod array composite material.

The invention discloses a lithium ion battery negative electrode material with a photochromic characteristic and a preparation method thereof. The molecular formula of the lithium ion battery negative electrode material with the photochromic characteristic is MVMo9O28. Wherein MV is a methyl viologen cation; according to the lithium ion battery negative electrode material with the photochromic characteristic, electron transfer from oxygen atoms to molybdenum atoms occurs under ultraviolet irradiation, and a two-year super-stable charge separation state is formed along with color change of crystals from colorless to blue; when the lithium ion battery negative electrode material with the photochromic characteristic is used as the lithium ion battery negative electrode material, the specific capacity of the battery can be improved in a colored state compared with an initial state; a new strategy is provided for developing a high-performance lithium ion battery negative electrode material, and the ever-increasing energy storage requirement is expected to be met.

The application discloses a gradient-doped BiVO4 / WO3 photoanode material and a preparation method and application thereof, and relates to the technical field of photoanode materials. 6+ The gradient-doped BiVO4 / WO3 photoanode material comprises a BiVO4 / WO3 heterojunction, and variable-valence transition metal ions are doped on the surface of the BiVO4 / WO3 heterojunction and the interface between BiVO4 and WO3, wherein the variable-valence transition metal ions comprise one of Mo 2+ and Co. The application adopts the above gradient-doped BiVO4 / WO3 photoanode material and the preparation method and application thereof, introduces variable-valence transition metal elements between the interface of BiVO4 and WO3, promotes the formation of an electron transport fast channel in a bulk phase, and improves the charge separation and transport efficiency of the BiVO4 / WO3 heterojunction interface; meanwhile, the variable-valence transition metal elements are constructed on the surface of the photoanode material, a CoOOH cocatalyst layer is formed on the surface, the cocatalyst layer and the interface electron transport fast channel synergistically act, the photo-generated charges of the BiVO4 / WO3 heterojunction bulk phase and surface are efficiently separated and transported, and therefore, the photo-catalytic efficiency is improved, and the service life of the photoanode material is prolonged.

The application discloses a functionalized gold-silver nanowire alloy composite photoelectric material and a preparation method and application thereof. A pillar[6]arene molecule AuAg@WP6 capable of undergoing host-guest complexation with a serotonin molecule 5- HT is wrapped on the surface of gold-silver nanowire alloy AuAg NWs, and the AuAg@WP6 / rGO-C3N4 is loaded on a reduced graphene oxide and carbon nitride rGO-C3N4 composite material to design a PEC biosensing system. The AuAg@WP6 / rGO-C3N4 serves as a sensing material. The LSPR effect of the AuAg NWs under visible light irradiation promotes charge separation. The host-guest complexation of the WP6 can selectively adsorb a large amount of 5- HT to the surface of the material. Since the g-C3N4 and the rGO have similar pi-conjugated structures, the two are easy to be bonded to form the rGO-C3N4 composite material. The photo-induced holes on the rGO-C3N4 can accelerate the oxidation of the serotonin molecule, and further improve the photocurrent response to detect 5- HT. Based on the excellent photoelectrochemical performance of the composite material, the linear range for detecting 5- HT is 0.01-100 muM, and the detection limit is 2 nM (S / N=3).

The invention discloses a photochromic TiO2-PEG200 (Polyethylene Glycol 200) nano particle and an application of the photochromic TiO2-PEG200 nano particle in photocatalytic oxidation of a C-H bond. The catalyst is synthesized through a solvothermal method, PEG200 is used as a solvent and a modifier, and self-doped Ti < 3 + > and surface oxygen vacancies are introduced into TiO2. Under the irradiation of blue light (405nm), the catalyst generates a photochromic effect, Ti < 4 + > is reduced into high-concentration Ti < 3 + > in situ, and meanwhile, a large amount of superoxide free radicals (O < 2 + >) are generated. A photo-generated hole directly activates an ethylbenzene alpha-C-H bond to generate a benzyl free radical, and the benzyl free radical reacts with a superoxide free radical (O2.) and is finally converted into acetophenone. The catalyst has excellent visible light response and charge separation efficiency, and the acetophenone yield is up to 56 mmol.g <-1 >. H <-1 > and is 10 times that of traditional TiO2. The reversible circulation of Ti < 3 + > / Ti < 4 + > enables the catalyst to maintain good stability, and the activity is still maintained at 95% or above after five times of circulation. The operation conditions are mild (room temperature and normal pressure), a strong oxidant is not needed, an efficient, stable and environment-friendly photocatalysis solution is provided for C-H bond activation, and the method has important application value in the field of fine chemical synthesis.

The invention relates to the technical field of semiconductors, in particular to a gallium oxide nanowire / porous gallium nitride heterojunction and a preparation method and application thereof. The method comprises the following steps: sequentially growing a GaN buffer layer, a u-GaN layer and a p-GaN layer on a substrate to obtain a base; in mixed gas of hydrogen and inert gas, performing thermal decomposition on the substrate to obtain porous gallium nitride; heating the porous gallium nitride in mixed gas of oxygen and inert gas to obtain a gallium oxide / porous gallium nitride heterojunction; spraying gold on the surface of the gallium oxide / porous gallium nitride heterojunction, and annealing the gold into gold particles in an inert atmosphere; in mixed gas of oxygen and inert gas, a gallium source is arranged beside the gallium oxide layer in the previous step for heating, and the gallium oxide nanowire / porous gallium nitride heterojunction is obtained. The prepared heterojunction has excellent carrier transport characteristics, light absorption efficiency and charge separation capability, and is suitable for the fields of solar-blind ultraviolet photoelectric detection, photocatalysis, high-sensitivity sensors, high-power electronic devices and the like.

The invention discloses an S-type heterojunction Bi2Sn2O7 / Bi4O5I2 composite photocatalyst and a preparation method thereof, the in-situ composite Bi2Sn2O7 / Bi4O5I2 composite photocatalyst is obtained through the preparation steps of magnetic stirring, hydrothermal treatment, centrifugal washing and the like, and the in-situ composite Bi2Sn2O7 / Bi4O5I2 composite photocatalyst is applied to a photocatalytic water treatment method to achieve efficient removal of pollutants. According to the Bi2Sn2O7 / Bi4O5I2 composite photocatalyst prepared by the preparation method disclosed by the invention, an inner electric field is formed through the construction of an S-type heterojunction between Bi2Sn2O7 and Bi4O5I2, an excitation transmission path of photogenerated electrons is changed under the action of the inner electric field, migration and conversion of photogenerated charges are promoted, and then compounding of photogenerated electron-hole pairs is inhibited. It is worthy of noting that the discrete heterojunction of the Bi2Sn2O7 quantum dot modified Bi4O5I2 hollow nanotube is designed and constructed, and separation and axial transportation of photo-generated charges can be achieved. The discrete structure is beneficial to spatial separation of redox reaction sites, is also beneficial to separation of photogenerated charges, and is an ideal strategy for improving the charge separation efficiency and photocatalytic activity of the semiconductor material. The apparent rate constant k and the rate constant (0.3463 min <-1 >) of the Bi2Sn2O7 / Bi4O5I2 heterojunction, which are obtained according to a fitting quasi-first-order kinetic equation, are 1.9 times and 58.7 times of those of a Bi4O5I2 hollow nanotube (k is equal to 0.1792 min <-1 >) and a Bi2Sn2O7 quantum dot (k is equal to 0.0059 min <-1 >) respectively. The invention provides a feasible method for preparing a high-performance photocatalyst, and provides a new idea for the design of heterojunction.

This invention relates to the field of photocatalysis technology, and more particularly to a photocatalyst, its preparation method, and its application. The invention provides a photocatalyst comprising CdSO4, h-CdS, and c-CdS in sequence; a heterojunction is formed between h-CdS and c-CdS, and a heterojunction is formed between CdSO4 and h-CdS. The photocatalyst effectively promotes photogenerated charge separation, suppresses electron-hole recombination, and significantly improves photocatalytic performance. Example results show that the photocatalyst provided by this invention achieves a water splitting rate of 12.4 mmol / h / g, which is 2.9 times higher than that of c-CdS.

The invention discloses a Bi2WO6 / g-C3N4 heterojunction photocatalyst as well as a preparation method and application of the Bi2WO6 / g-C3N4 heterojunction photocatalyst. The Bi2WO6 / g-C3N4 heterojunction photocatalyst is prepared from Bi2WO6 particles and a g-C3N4 nanosheet, and a Z type heterojunction is formed between the Bi2WO6 particles and the g-C3N4 nanosheet. According to the Bi2WO6 / g-C3N4 (BCN) photocatalyst, through collaborative optimization of a heterojunction structure and surface engineering, the visible light absorption range is widened, the charge separation efficiency is improved, and active sites are enriched, the catalyst has rich surface hydroxyl groups and oxygen vacancies and a hierarchical mesoporous structure, the adsorption capacity on ZEN is enhanced, and the photocatalytic activity of the photocatalyst is improved. Separation and transfer of photon-generated carriers are promoted, and catalytic reaction kinetics is improved; compared with single g-C3N4 or Bi2WO6, the degradation rates of ZEN are respectively increased by 2.51 times and 12.57 times, and the degradation efficiency reaches 99.4%.

This invention discloses a frustum-shaped flexible photoelectric energy conversion module, comprising an optical fiber connector, a housing, and a photovoltaic cell. The optical fiber connector is fixedly disposed on the top of the housing. A frustum-shaped cavity is formed within the housing, and the photovoltaic cell is fixed within the cavity. The photovoltaic cell is a three-dimensional flexible energy transfer chip comprising multiple sub-cells connected in series. Each sub-cell comprises multiple arrayed nanowires with a radial PIN structure. A wire interface is provided on the housing. The input end of the photovoltaic cell is connected to an external input device via the optical fiber connector, and the output end of the photovoltaic cell passes through the wire interface and is connected to a power-consuming device. In this invention, the use of a nanowire array structure for the sub-cells increases the specific surface area, expands the longitudinal absorption area, saves projected area, reduces volume, and improves heat dissipation. Simultaneously, the nanoarray structure can significantly improve the light-harvesting capability and charge separation efficiency of the cell.

The invention belongs to the field of photocatalysis, and particularly discloses a perovskite composite photocatalyst for photocatalytic ethanol dehydrogenation and application. The composite photocatalyst takes a CdS nanorod as a carrier, a Cs2AgBiBr6 double perovskite active component formed by CsBr, AgBr and BiBr3 precursors is loaded on the surface of the CdS nanorod through a vacuum in-situ growth method, and a Pt, Rh or Ni metal cocatalyst can be further loaded. The method comprises the following steps: dispersing a CdS nanorod and a perovskite precursor in a mixed organic solvent, carrying out vacuum freezing-air exhaust circulation treatment, and removing the solvent under a heating condition to prepare the composite photocatalyst. When the photocatalyst is used for an ethanol photocatalytic dehydrogenation reaction under an anaerobic condition, hydrogen, acetaldehyde and acetal can be efficiently generated under the irradiation of visible light. According to the method, the photo-generated charge separation efficiency and the reaction stability are remarkably improved, and a new way is provided for ethanol high-valued conversion.