156 results about "Cadmium sulphide" patented technology

The invention relates to a heterojunction composite material and a preparation method and application thereof, and belongs to the technical field of catalysts. The preparation method of the heterojunction composite material comprises the following steps: dispersing nano cadmium sulfide in water to obtain a nano cadmium sulfide dispersion liquid, then adding a triazinyl covalent organic framework, fully reacting at 75-85 DEG C, centrifuging, precipitating, washing and drying to obtain the heterojunction composite material. The narrow-band-gap semiconductor cadmium sulfide and the wide-band-gap semiconductor triazinyl covalent organic framework are compounded to form the heterojunction structure composite material photocatalyst, and the narrow-band-gap semiconductor cadmium sulfide and the wide-band-gap semiconductor triazinyl covalent organic framework interact with each other, so that the response range of sunlight is widened, separation and transfer of photo-induced electrons and holes are promoted, and the photoelectric conversion efficiency is improved. Therefore, the photocatalytic oxidation-reduction capacity of the catalyst is improved, and the photocatalytic performance of the catalyst is finally improved. The heterojunction composite material can be applied to the field of cleaning and environmental protection as a photocatalyst, and has excellent hydrogen production efficiency.

A dual-modal information storage and anti-counterfeiting material, and its preparation method are provided. The dual-modal information storage and anti-counterfeiting material uses cadmium sulfide quantum dots (CdS QDs) as information storage material, and uses the controllable photocorrosion of CdS QDs to achieve dual-modal optical information storage and anti-counterfeiting applications. Firstly, the type of ligands and modification degree of CdS QDs are precisely controlled during the aqueous phase synthesise process, so as to effectively control the photocorrosion phenomenon under UV light irradiation. Subsequently, the CdS QDs are loaded in the hydrogel network, and they are also loaded on the substrates such as cloth and paper by spray coating, dip coating or 3D printing, and the information is stored by digital light patterning. Different from the photochromic function of traditional anti-counterfeiting material, the CdS QDs shows dual-modal patterning characteristics in a wide wavelength range.

A photovoltaic device is presented. The photovoltaic device includes a layer stack; and an absorber layer is disposed on the layer stack. The absorber layer comprises selenium, wherein an atomic concentration of selenium varies across a thickness of the absorber layer. The photovoltaic device is substantially free of a cadmium sulfide layer.

The invention discloses a preparation method of a three-dimensional flower-cluster-shaped CdS QDs (at) ZnS / ZnO composite photocatalyst, belongs to the field of preparation of photocatalytic materials, and aims to solve the problem of relatively low photocatalytic efficiency. The preparation method comprises the following steps: 1, preparing zinc oxide: dissolving Zn (CH3COO) 2.2 H2O in deionized water, stirring until Zn (CH3COO) 2.2 H2O is completely dissolved, adding NaOH, stirring to form an emulsion, transferring the mixed emulsion into a polytetrafluoroethylene reaction kettle, and treating at 160 DEG C for 10 hours; 2, preparation of cadmium sulfide quantum dots (CdS QDs): dropwise adding thioacetamide (TAA) into a Cd (NO3) 2.4 H2O aqueous solution, continuously stirring and dropwise adding a NaOH solution, adjusting the pH value of the solution to 10.5, then adding a Na2S solution, stirring at 65 DEG C for 1 h, cooling to room temperature, and aging for 24 h; and 3, dissolving Zn (CH3COO) 2.2 H2O and TAA in deionized water, adding ZnO powder, adding CdS QDs, and carrying out rapid stirring. Putting into a microwave reaction instrument, reacting at 160 DEG C for 45 minutes, washing and drying. The three-dimensional flower-cluster-shaped CdS QDs (at) ZnS / ZnO composite photocatalyst is prepared through a microwave-assisted hydrothermal method, and the photocatalytic oxidation performance is effectively improved.

The present invention discloses a preparation method and application of a cadmium sulfide nanotube array catalyst. First, a cadmium sulfide nanorod array is prepared on a conductive glass by a hydrothermal method; then, a cadmium sulfide nanotube array catalyst is prepared by etching the cadmium sulfide nanorod array using a photolithography method. The cadmium sulfide nanotube array catalyst prepared by the present invention utilizes the excellent visible light absorption characteristics of cadmium sulfide to improve the light energy utilization rate, and uses a tubular nanostructure with a large specific surface area to increase the active area of the photoelectrocatalytic water splitting reaction, effectively promoting the separation and transmission of photogenerated carriers, inhibiting the recombination of photogenerated carriers, and showing excellent photoelectrocatalytic water splitting hydrogen production performance. The process of the present invention is simple, the synthesized substance has high purity, the size is at the nanometer level, and the raw materials used are cheap, which is suitable for the field of photoelectrocatalytic water splitting hydrogen production.

The invention provides a preparation method of a red light perovskite quantum dot with a core-shell structure, and belongs to the technical field of quantum dot preparation. According to the method, a CsPbI3 quantum dot coarse solution and a cadmium sulfide precursor solution are mixed, stirred and heated to a certain temperature, cadmium sulfide grows on the surface of the quantum dot in an epitaxial mode, the red light CsPbI3 / CdS core-shell quantum dot is prepared, the formation of a core-shell structure is beneficial to passivation of defects on the surface of the quantum dot, and meanwhile ion migration and Auger recombination of the quantum dot are inhibited. The invention provides a solution for preparing the red light perovskite quantum dot light-emitting diode with high external quantum efficiency, long service life and low efficiency roll-off.

The invention discloses a carbon nano tube / layered double hydroxide / cadmium sulfide composite photocatalyst as well as a preparation method and application thereof, and belongs to the technical field of hydrogen desorption by photocatalysis of water. The mass fraction of the carbon nano tube in the composite photocatalyst is 0.02%-0.04%, the mass fraction of the layered double metal hydroxide in the composite photocatalyst is 46.96%-51.98%, and the mass fraction of the cadmium sulfide in the composite photocatalyst is 48%-53%. According to the invention, Co-ZIF is anchored on a carbon nanotube by using carboxyl groups on the surface of an acid functionalized carbon nanotube; in the etching process, the surface of the CNT / Co-ZIF is roughened and a layered structure is generated by utilizing ion exchange and hydration reaction, so that the Co-ZIF is converted into CoMo-LDH; after the cocatalyst CNT / CoMo-LDH is compounded with CdS, the cocatalyst CNT / CoMo-LDH not only has good morphology and dispersity, but also accelerates electron transfer and improves the separation and migration efficiency of photo-induced electrons-holes by virtue of the serially connected carbon nanotubes, so that the photocatalytic water decomposition and hydrogen evolution performance of the nano semiconductor CdS is improved.

The invention discloses a composite photocatalyst for removing uranium in nuclear waste liquid and a preparation method thereof, and the preparation method comprises the following steps: dropwise adding a solution B dissolved with Na2S. 9H2O into a solution A dissolved with CdCl2. 5H2O to obtain a mixed solution; heating the mixed solution for reaction; after cooling to room temperature, centrifuging and washing a product; freeze-drying the washed product overnight to obtain cadmium sulfide; dispersing cadmium sulfide to obtain a suspension; agNO3 is added into the suspension liquid; heating the suspension to react; and washing for several times, and freeze-drying to obtain the silver-loaded cadmium sulfide composite photocatalyst with the cadmium vacancy. The prepared composite photocatalyst is used for adsorption and photo-reduction treatment of radioactive uranium in nuclear waste liquid, and efficient photocatalytic removal of uranium in uranium waste water within the pH value range of 4-8 is achieved. On the premise of being green and environment-friendly, only light and a photocatalyst are needed, pollution to the environment is avoided, operation is easy and convenient, the reaction condition is mild and not harsh, the reaction catalyst can be recycled, and cost is saved.

The invention discloses a modified hollow cadmium sulfide photocatalytic reducing agent and a preparation method and application thereof, and belongs to the technical field of wastewater treatment.The preparation method comprises the steps that silicon dioxide microspheres and deionized water are mixed to prepare suspension liquid, a sodium citrate aqueous solution, a cadmium chloride aqueous solution, ammonia water and a thiourea aqueous solution are added into the suspension liquid, the mixture is stirred to be uniform and then heated for a reaction, and the modified hollow cadmium sulfide photocatalytic reducing agent is obtained; preparing to obtain a silicon dioxide and cadmium sulfide composite material; immersing the silicon dioxide and cadmium sulfide composite material into a sodium hydroxide solution, heating and etching to obtain nano hollow cadmium sulfide; the preparation method comprises the following steps: immersing nano hollow cadmium sulfide into a 1-octadecene solution, carrying out heating reaction, and carrying out alcohol washing and drying to obtain the modified hollow cadmium sulfide photocatalytic reducing agent. The modified hollow cadmium sulfide composite photocatalyst is synthesized through a silicon dioxide template method and a thermal decomposition method, and high-concentration methyl orange industrial wastewater can be efficiently degraded under the condition of visible light irradiation.

The present invention discloses a method for photocatalytic dehydration condensation of biomass platform small molecule furfural and its derivatives with aldehydes / ketones. The method uses water-soluble cadmium sulfide quantum dots doped with proline as a photocatalyst, and biomass platform small molecule furfural and its derivatives and aldehydes / ketones as substrates, aiming to achieve photocatalytic dehydration condensation of biomass platform small molecule furfural and its derivatives with aldehydes / ketones in an aqueous phase system. The photocatalyst of the present invention is synthesized using cheap and easily available raw materials by a simple and easy-to-operate experimental method. This photocatalytic reaction does not require the use of noble metal materials as co-catalysts, and can achieve dehydration condensation to construct C═C under mild conditions. The products can be applied in fields such as spices and aviation fuel.

The invention belongs to the field of photocatalytic materials, and particularly relates to a silver metavanadate composite cadmium sulfide photocatalytic material as well as a preparation method and application thereof in photocatalytic hydrogen production. The preparation method comprises the following steps: taking a sulfur source and a cadmium source, adding ethylenediamine, and uniformly stirring and mixing; transferring the mixture into a hydrothermal reaction kettle for reaction, after the reaction is finished, obtaining turbid liquid, and centrifugally washing and drying the turbid liquid to obtain cadmium sulfide powder; the preparation method comprises the following steps: adding water into cadmium sulfide, adding a silver source and a vanadium source under a stirring condition, stirring, transferring into a reaction kettle, carrying out a hydrothermal reaction, centrifuging, washing and drying to obtain the silver metavanadate composite cadmium sulfide photocatalytic material. The photocatalytic material disclosed by the invention has a relatively obvious catalytic effect in a photocatalytic hydrogen production reaction. Under the irradiation of a xenon lamp and under the condition of a set reaction system, the hydrogen production rate of water decomposition of the photocatalyst reaches 228.8 mu mol / g / h, which is obviously superior to that of a pure cadmium sulfide catalyst.

The invention provides a preparation method and application of a polycrystalline molybdenum carbide / cadmium sulfide composite catalyst. The material has excellent performance in the aspect of hydrogen production by photocatalytic decomposition of water. The preparation method comprises the following steps: firstly, taking melamine, cyanuric acid and ammonium molybdate as raw materials, and annealing in an inert atmosphere in a tubular furnace to prepare polycrystalline molybdenum carbide; then taking cadmium nitrate, thiourea and ethidene diamine as raw materials to hydrothermally prepare cadmium sulfide in a polytetrafluoroethylene high-pressure reaction kettle; and finally, dispersing the polycrystalline molybdenum carbide and cadmium sulfide in N, N-dimethylformamide, and carrying out ultrasonic treatment, stirring, washing and drying to obtain the polycrystalline molybdenum carbide / cadmium sulfide. According to the polycrystalline heterostructure disclosed by the invention, a channel for directionally and rapidly transferring current carriers is constructed, the separation of electron-hole pairs is accelerated, and the migration rate of electrons is improved; meanwhile, a molybdenum vacancy located at a crystal boundary forms a Lewis acid site serving as an active site of a hydrogen production reaction, so that an energy barrier of the hydrogen production reaction is reduced, and excellent performance of photocatalytic decomposition of water to produce hydrogen is shown.

The invention discloses a method for preparing alanine by photoreforming polylactic acid plastic, which is characterized by comprising the following steps: placing polylactic acid plastic and a photocatalyst in ammonia water to obtain a reaction solution, and adding the reaction solution into a light-transmitting reactor; and in an inert atmosphere, irradiating the reaction liquid with a light source at 60-80 DEG C for 5-20 hours, and carrying out a photocatalytic reaction to obtain the alanine. According to the method, the process of catalyzing the polylactic acid plastic to be converted into the alanine is achieved through the one-step method with the self-made cobalt phosphide / cadmium sulfide as the photocatalyst, high selectivity and stability are achieved, meanwhile, the method is simple in process, raw materials are easy to obtain, reaction conditions are mild, separation and purification operation is easy, and high economic value and application value are achieved.

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 an oxide-sulfide S-type heterojunction composite photocatalyst as well as a preparation method and application thereof. x The oxide-sulfide S-type heterojunction composite photocatalyst is prepared by adding WO x into ethanol, uniformly ultrasonic dispersing, and then performing heating and dry distillation. The application successfully constructs a tungsten oxide and cadmium sulfide heterojunction, has good light response, utilizes a heterojunction interface formed by the two catalysts and having a synergistic effect, improves the photocatalytic hydrogen production capacity, and promotes selective oxidation of benzyl alcohol. The application has simple operation and good repeatability.

The invention relates to a method for preparing a boronized carbonyl derivative by catalyzing an alpha, beta-unsaturated carbonyl derivative with a heterogeneous photocatalyst, which comprises the following steps: by taking the alpha, beta-unsaturated carbonyl derivative and N-heterocyclic carbene borane as raw materials and cadmium sulfide as the heterogeneous photocatalyst, reacting for 1-100 hours at 0-80 DEG C in an inert atmosphere and under the illumination condition, thereby obtaining the boronized carbonyl derivative. The product borylated carbonyl derivative is obtained. The alpha-boron substituted compound is prepared by adopting the heterogeneous photocatalyst for the first time, the reaction condition is mild, and the catalyst can be recycled.

A dual-modal information storage and anti-counterfeiting material, and its preparation method are provided. The dual-modal information storage and anti-counterfeiting material uses cadmium sulfide quantum dots (CdS QDs) as information storage material, and uses the controllable photocorrosion of CdS QDs to achieve dual-modal optical information storage and anti-counterfeiting applications. Firstly, the type of ligands and modification degree of CdS QDs are precisely controlled during the aqueous phase synthesise process, so as to effectively control the photocorrosion phenomenon under UV light irradiation. Subsequently, the CdS QDs are loaded in the hydrogel network, and they are also loaded on the substrates such as cloth and paper by spray coating, dip coating or 3D printing, and the information is stored by digital light patterning. Different from the photochromic function of traditional anti-counterfeiting material, the CdS QDs shows dual-modal patterning characteristics in a wide wavelength range.

The application discloses a kind of passivated antimony selenide (Sb2Se3) thin film solar cell and preparation method, the cell from bottom to top includes in turn: indium tin oxide (ITO) transparent conductive glass front electrode substrate, cadmium sulfide (CdS) electron transport layer, Sb2Se3 absorption layer, polyvinylidene fluoride-trifluoroethylene copolymer P (VDF-TrFE) passivation layer and gold (Au) back electrode layer.The passivated antimony selenide (Sb2Se3) thin film is P (VDF-TrFE) thin film in Sb2Se3 absorption layer surface spin coating, and the surface deep level defect of passivation film is passivated.The advantages of the application are that the scientific problem that Sb2Se3 semiconductor thin film surface deep level defect causes Sb2Se3 solar cell open-circuit voltage to be low is successfully solved by P (VDF-TrFE) thin film strategy, so as to improve the performance of Sb2Se3 thin film solar cell.This innovative technology provides an important technical solution for preparing high-efficiency and low-cost Sb2Se3 thin film solar cell.

The invention discloses an anti-fouling and anti-corrosion coating based on a quantum dot material as well as a preparation method and application thereof, and relates to the technical field of corrosion and biological fouling control of hydraulic structures and marine equipment materials. The anti-fouling and anti-corrosion coating based on the quantum dot material comprises organic bonding resin, a curing agent and the quantum dot material, and the mass ratio of the organic bonding resin to the curing agent to the quantum dot material is (3-5): (5-7): (0.005-0.05); wherein the quantum dot material comprises at least one of a copper sulfide quantum dot material, a zinc sulfide quantum dot material, a cadmium sulfide quantum dot material and a composite quantum dot material, and the particle size of the copper sulfide quantum dot material, the zinc sulfide quantum dot material and the cadmium sulfide quantum dot material is smaller than 20 nm. The coating provided by the technical scheme of the invention has excellent anti-corrosion and anti-fouling effects and relatively long service life.

The invention provides a method for high-selectivity preparation of synthesis gas and glyoxylic acid through photocatalysis of PET plastic. According to the method, the selectivity of a liquid product obtained by photocatalysis of the PET plastic is remarkably improved by controlling a single active oxygen species (specifically holes), and high-selectivity oxidation is realized. Furthermore, the proportion of carbon monoxide to hydrogen in the generated synthesis gas can be changed by regulating and controlling the mass ratio of cadmium sulfide to nickel aluminum hydrotalcite in the heterojunction composite material formed by compounding cadmium sulfide and nickel aluminum hydrotalcite. The method has the characteristics of low preparation cost, stable catalyst performance, simple preparation process, convenience in operation, environmental protection and the like, and has a very good application prospect.

The invention discloses a preparation method and application of a cadmium sulfide nanotube array catalyst, and the preparation method comprises the following steps: firstly, preparing a cadmium sulfide nanorod array on conductive glass by using a hydrothermal method; and then etching the cadmium sulfide nanorod array by utilizing a photoetching method to prepare the cadmium sulfide nanotube array catalyst. According to the prepared cadmium sulfide nanotube array catalyst, the excellent visible light absorption characteristic of cadmium sulfide is utilized, the light energy utilization rate is increased, the tubular nanostructure with the large specific surface area is utilized, the active area of the photoelectrocatalytic water decomposition reaction is increased, separation and transmission of photon-generated carriers are effectively promoted, compounding of the photon-generated carriers is inhibited, and the photocatalytic activity of the photoelectrocatalytic water decomposition reaction is improved. The excellent performance of producing hydrogen by photoelectrocatalytic decomposition of water is shown. The method has the advantages of simple process, high purity of the synthesized substance, nanoscale size and cheap raw materials, and is suitable for the field of hydrogen production by photoelectrocatalytic decomposition of water.

The application discloses a kind of hollow microspheres of titanium dioxide / cadmium zinc sulfide heterojunction with zinc, oxygen double vacancies, the preparation method of the catalyst of the hollow microspheres of titanium dioxide / cadmium zinc sulfide heterojunction and the catalyst application of the hollow microspheres of titanium dioxide / cadmium zinc sulfide heterojunction.The hollow microspheres of titanium dioxide / cadmium zinc sulfide heterojunction with zinc, oxygen double vacancies of the application, the preparation method of the catalyst of the heterojunction hollow microspheres and the preparation method of the application of the double vacancies heterojunction hollow microspheres are in situ preparation method using one-step hydrothermal method, and double vacancies heterojunction is constructed on the surface of titanium dioxide hollow microspheres, which has the advantages of high activity stability, simple preparation process and controllable reaction conditions.The heterojunction hollow microspheres have wide visible light absorption range, low photo-generated charge recombination rate, and exhibit excellent photocatalytic reduction of carbon dioxide and photocatalytic oxidation of benzyl alcohol activity and good stability.

The invention relates to the technical field of solar cells, and discloses a method for preparing a semiconductor thin film solar cell, which comprises the following steps of: S1, cleaning a substrate: carrying out ultrasonic cleaning on the substrate by using deionized water, alcohol and alkali liquor in sequence; s2, positive electrode deposition: depositing a molybdenum film on the substrate through a magnetron sputtering method; s3, preparing a precursor film: preparing the precursor film by using a sol-gel method; s4, selenylation annealing: putting the precursor film, selenium particles and tin disulfide into a graphite box; s5, buffer layer deposition: depositing a cadmium sulfide buffer layer on the absorption layer through a chemical bath method; s6, depositing a window layer; s7, depositing a negative electrode; and S8, packaging. The tin disulfide atmosphere is introduced in the annealing process, element distribution and crystal quality of the copper-zinc-tin-sulfide thin film are further optimized, composition segregation is effectively inhibited, and the composite defect density in the material is reduced. And the absorption layer has more excellent crystallization characteristics, so that the photoelectric conversion efficiency is remarkably improved.

The invention provides a preparation method of a carbon quantum dot / phosphotungstic acid / cadmium sulfide composite photocatalyst, and belongs to the technical field of photocatalytic degradation and water photolysis hydrogen production. Comprising the following steps: dissolving a cadmium source and a sulfur source in an ethylenediamine solution, stirring the mixture until the mixture is uniform, carrying out hydrothermal reaction, and treating a product to obtain cadmium sulfide solid powder; the preparation method comprises the following steps: adding a carbon source into deionized water, performing ultrasonic treatment, performing microwave reaction, and filtering, washing and drying a product to obtain carbon quantum dot solid powder; the preparation method comprises the following steps: mixing phosphotungstic acid, cadmium sulfide solid powder and carbon quantum dot solid powder in deionized water, uniformly stirring, carrying out hydrothermal reaction, and centrifuging, filtering and washing a product to obtain the carbon quantum dot / phosphotungstic acid / cadmium sulfide composite photocatalyst. The photocatalytic performance of cadmium sulfide is effectively improved, the degradation effect on organic pollutants is excellent, the strong water photolysis hydrogen evolution effect is achieved, the preparation technology is simple, cost is low, and industrial application and environment restoration are facilitated.

The invention provides a method for high-efficiency electrocatalytic reduction of carbon dioxide by an ionic liquid system cooperating with a cadmium sulfide catalyst. The electrocatalytic reduction process of the method is carried out by placing a three-electrode system in an H-shaped electrolytic cell filled with ionic liquid. The three-electrode system comprises a reference electrode, a counter electrode and a working electrode, the silver / silver ion electrode is the reference electrode, the platinum net electrode is the counter electrode, and a cadmium sulfide catalyst which is loaded on carbon paper and has a large specific surface area and high conductivity is the working electrode. The method specifically comprises the following steps: mixing a cadmium sulfide catalyst with acetone, adding a Nafion solution, carrying out ultrasonic treatment to obtain a uniformly mixed suspension, uniformly dispensing the suspension on carbon paper, and naturally airing at room temperature to obtain a working electrode; and placing the working electrode in the ionic liquid-acetonitrile-aqueous solution electrolyte, and continuously introducing carbon dioxide gas to carry out a constant-potential electrochemical reduction reaction. The electro-catalysis system is easy to operate and mild in reaction condition, the preparation method of the cathode catalyst is simple, industrial development value is achieved, and an important and practical way is provided for fixation and recycling of carbon dioxide.

The application relates to application of Bi2O2Se in a photocatalytic nitrogen fixation reaction and belongs to the technical field of photocatalytic nitrogen reduction. The BOS catalyst with intrinsic weak hole oxidation capacity realizes efficient and stable photocatalytic ammonia synthesis without a sacrificial agent. The BOS has an optimized narrow band gap structure and a unique straddling energy band arrangement, the valence band position is shallow, the hole oxidation capacity is weak, the oxidation degradation of NH4 + Can be effectively inhibited, and the conduction band position is suitable, so that the thermodynamic driving force of nitrogen reduction is ensured. The catalyst has excellent light absorption capacity in a wide spectral range (extending to the near-infrared region), and the apparent quantum efficiency reaches 0.12% at a wavelength of 700 nm. The ammonia synthesis rate of the BOS without a sacrificial agent reaches 61 muM.h ‑1 -1, which is 8.3 times and 2.8 times that of carbon nitride and cadmium sulfide, and the catalyst maintains high activity in an air atmosphere, has excellent oxygen compatibility and cycle stability.

The invention discloses a simple preparation method of a monocluster polyacid / three-dimensional ordered macroporous cadmium sulfide coupled catalyst for efficient photocatalytic water desorption of hydrogen. Single-cluster uniform dispersion of Sb9 on 3DCdS is realized by a room-temperature impregnation method, and the coupling material is simple in preparation method, mild in reaction condition and low in cost. Under the driving of visible light, the hydrogen desorption yield of water within 6 hours can reach 206.2 [mu] mol, which is 9 times of that of single 3DCdS. The high specific surface area and the stable macroporous structure of the material expose more active centers for the reaction, the carried Sb9 effectively inhibits carrier recombination, the catalytic activity of the catalyst in photocatalysis is further improved, and the material has a good application prospect.

The invention relates to the technical field of photocatalysts, in particular to a metal monatomic / polydopamine / cadmium sulfide composite material and a preparation method and application thereof. The composite material takes cadmium sulfide nanoparticles wrapped by polydopamine as a matrix and is loaded with metal single atoms. The composite material generates electron-hole pairs and is separated under the excitation of visible light, holes are distributed on a valence band of CdS, electrons are distributed on a conduction band of CdS, the electrons distributed on the conduction band of CdS are transferred to the surfaces of metal monoatoms through polydopamine, finally, photo-generated electrons are distributed on the metal monoatoms, and photo-generated holes are distributed on the valence band of CdS. When a reaction occurs, oxygen is oxidized into superoxide ions by metal single atoms, water is reduced into H < + > by holes in a CdS valence band, the H < + > is transferred to the metal surface by polydopamine, and OOH is generated by combining. O2 <-> and photo-induced electrons loaded on the metal surface with the H < + >; further combining with H < + > to generate H2O2.

The invention relates to the technical field of photocatalysis, and discloses a three-way catalytic material, a preparation method and application thereof, a method for producing hydrogen through water decomposition and a method for producing hydrogen through ammonia decomposition. The invention relates to a three-way catalytic material. The three-way catalytic material comprises a carbon nitride matrix, iron oxide and cadmium sulfide, wherein the iron oxide and the cadmium sulfide grow on the carbon nitride matrix in a cluster form; the average particle size of the iron oxide and cadmium sulfide clusters is 40-80 nm. The three-way catalytic material has good catalytic activity, and the photocatalytic hydrogen production performance can be improved.

The present invention discloses a quantum dot laser with a low threshold and a preparation method thereof, which includes a quartz substrate, a silica periodic grating, a quantum dot layer, and a silica protective layer stacked in sequence. The quantum dot layer is composed of closely packed mercury selenide quantum dots with a diameter of 4.8 nm to 6.6 nm, mercury sulfide quantum dots with a diameter of 4 nm to 5.2 nm, quantum dots with a core / alloy / shell structure of mercury selenide / mercury cadmium selenide / cadmium selenide with an effective exciton diameter of 4.8 nm to 6.4 nm, or quantum dots with a core / alloy / shell structure of mercury sulfide / mercury cadmium sulfide / cadmium sulfide with an effective exciton diameter of 4 nm to 5 nm. The present invention realizes environmentally stable electron doping in quantum dots by controlling the size of the quantum dots, uses the doped quantum dots as the gain medium of the laser, and further realizes a low gain threshold, a low laser threshold, sustainable continuous laser output, and a designable output wavelength.