49results about How to "Enhance photocatalytic hydrogen production activity" patented technology

The invention discloses a carbon dot / carbon nitride / titanium dioxide composite material which is formed by compounding of three-phase carbon dots, graphene-like carbon nitride and titanium dioxide, wherein carbon nitride has a large surface area so as to just provide a depositing space for titanium dioxide nanosheets, so that titanium dioxide cannot cluster; and meanwhile, carbon nitride has relatively narrow energy gap and can increase the light response range. Furthermore, compounding of photo-induced electrons can be further inhibited by utilizing the unique electron transfer capacity of carbon dots, so as to increase the photocatalytic capacity. Moreover, the preparation method is mild in process conditions and low in cost, and the composite material is suitable for large-scale production, and has wide application prospect.

The invention discloses a photocatalyst based on graphite phase carbon nitride g-C3N4, and a preparation method and an application thereof. The photocatalyst based on graphite phase carbon nitride g-C3N4 has a high photocatalytic hydrogen production activity, the hydrogen production activity is higher than 600 [mu]mol.g<-1>.h<-1>, and the photocatalytic hydrogen production activity of bulk phase graphite phase carbon nitride g-C3N4 is significantly improved. The preparation method of the photocatalyst based on the graphite phase carbon nitride g-C3N4 comprises the following steps: preparing g-C3N4 nano-sheets from the bulk phase g-C3N4 by physical or chemical treatment, and calcining the g-C3N4 nano-sheets at a high temperature to prepare the photocatalyst based on graphite phase carbon nitride g-C3N4, with different photocatalytic activities. The preparation method has the advantages of simplicity, short operation cycle, low cost, and suitableness for large-scale industrial production. The photocatalyst based on graphite phase carbon nitride g-C3N4 can be used in the fields of photocatalytic water decomposition for hydrogen production, photocatalytic carbon dioxide reduction, fueldegradation, pollutant degradation and the like.

The invention discloses a preparation method of a precious-metal-free high-activity photocatalytic-water-splitting hydrogen-producing catalyst. In the invention, photocatalytically hydrogen-producing activities of a precious-metal-free NiOx-CdS photocatalyst, a precious-metal-free Ni-CdS photocatalyst and a precious-metal-free flower-shaped Ni / Ni(OH)2-CdS photocatalyst are all better than that of Pt-CdS, wherein the NiOx-CdS photocatalyst, the Ni-CdS photocatalyst and the Ni / Ni(OH)2-CdS photocatalyst are prepared respectively through an in-situ photodeposition method, a hydrothermal reduction method and a hydrothermal method. NiOx and Ni can effectively transfer and separate photoproduced electronics and holes so that the photocatalytically hydrogen-producing activity of the catalyst is enhanced. In addition, because of an unique flower-shaped structure of the flower-shaped Ni / Ni(OH)2, CdS can be inserted into a laminated structure of the Ni / Ni(OH)2 well and be contacted tightly with the Ni / Ni(OH)2, thereby forming a composite catalyst having an excellent photocatalytically hydrogen-producing activity under a photochemical effect.

The invention discloses a preparation method and an application of a highly crystallized carbon nitride photocatalytic material, and belongs to the technical field of semiconductor photocatalytic materials. The method comprises the following steps: 1) calcining melamine in a muffle furnace to obtain a heptazine precursor; 2) grinding and uniformly mixing the heptazine precursor, potassium salt andlithium salt, and calcining the mixture in the muffle furnace; 3) taking out the calcined product, and cleaning and drying the calcined product to obtain crystallized carbon nitride; and 4) dispersing the obtained crystallized carbon nitride in hydrochloric acid, continuously stirring the system, and finally washing and drying the system to obtain the highly crystallized carbon nitride photocatalytic material. In the invention, the crystallized carbon nitride is treated in the hydrochloric acid aqueous solution, so that the crystallinity of the obtained carbon nitride is greatly enhanced. Thehigh-crystallinity carbon nitride has great advantages in the aspects of photo-generated carrier migration and photo-generated electron hole pair inhibition. Meanwhile, potassium ions embedded into the high-crystallization carbon nitride middle layer make great contribution to migration of photo-induced electrons. Based on the two characteristics, the photocatalytic hydrogen production activity of the high-crystalline carbon nitride is greatly enhanced.

The invention aims at providing a composite semiconductor photocatalyst and an application thereof and relates to the field of photocatalytic materials. The photocatalyst is prepared by adopting the following method which comprises the following steps: preparing a precursor solution; mixing the precursor solution, a dispersing agent and a solvent, stirring and reacting for 0.5-5h at the temperature of 20-50 DEG C, and removing the solvent to obtain gel; firstly, treating the gel under the protection of nitrogen, then grinding, carrying out acid washing and water washing, and drying to obtain the composite semiconductor photocatalyst. The invention also provides the application of the composite semiconductor photocatalyst in the aspect of degrading organic pollutants and making hydrogen by water decomposition. The composite semiconductor photocatalyst has the advantages that the transferring distance between CdS and TiO2 is shortened, the photocorrosion rate of the surface of the CdS is reduced, not only can the dispersing effect of the CdS on the surface of the TiO2 be improved, but also the service life of the CdS is prolonged, and simultaneously the photocatalytic activity of the CdS is improved.

The invention discloses a visible light driven photocatalysis hydrogen production catalyst as well as a preparation method and application thereof. According to the technical scheme of the invention, tetraisopropyl titanate and tantalum-containing polyacid Ta-POMs-1 are adopted as precursors, the photocatalysis hydrogen production catalyst Ta-POM-1 / TiO2 is prepared by using a sol-gel method; and by optimizing and selecting types and amounts of dye molecules, types and amounts of sacrifice catalysts and amounts of the catalyst, the reaction conditions of catalysis hydrogen production with visible light, of the catalyst, can be optimized. Compared with parent TiO2 and POMs, a prepared Ta-POM-1 / TiO2 composite photocatalysis material is relatively good in visible light absorption and relatively high in photocatalysis hydrogen production activity, so that the visible light driven photocatalysis hydrogen production catalyst is relatively good in application prospect in the field of photocatalysis.

The invention provides a sulfide nano heterojunction. The nano heterojunction includes copper, indium, zinc, and cadmium, and the expression of the elements is Cu-In-Zn-S / CdS. The present invention accordingly provides a preparation method of the nano heterojunction, comprising the following steps: step A, mixing raw materials of copper acetylacetonate, indium acetylacetonate, zinc acetylacetonate and an Ag2S catalyst decomposed from silver thiocarbamate in a first mixed solvent to resolve and dissolve Cu-In-Zn-S nanorods, wherein the first mixed solvent includes octadecene; and step B, and adding a cadmium thiocarbamate compound and a second mixed solvent to the Cu-In-Zn-S nanorods to form a Cu-In-Zn-S / CdS nano heterojunction. The preparation method provided by the present invention is simple, suitable for industrial production, and high in yield, and the yield of the nano-heterojunction is up to 80%.

The invention discloses a thienyl polymer-containing photocatalyst with high photocatalytic water splitting hydrogen production activity and a preparation method thereof. The photocatalyst is prepared by adopting a simple ternary copolymerization Suzuki coupling reaction, and the construction unit of the photocatalyst comprises pyrene, thiophene or thiophene derivative and dibenzothiophene sulfone. The pyrenyl monomer and the dibenzothiophene sulfuryl monomer for polymerization have the same polymerizable functional groups and can be subjected to Suzuki coupling reaction with thiophene or thiophene derivative monomers at the same time so as to ensure that pyrenyl units and dibenzothiophene sulfuryl units in the polymer structure are connected through thiophene or thiophene derivative units. The polymer photocatalyst has the characteristics of high photocatalytic hydrogen production activity, high apparent quantum efficiency, narrow optical band gap and continuous and adjustable structure and composition, is simple in preparation process, high in yield and stable in performance, can release hydrogen under sunlight, and can be used in the field of photocatalytic hydrogen production.

The invention discloses a heterojunction photocatalyst for hydrogen production and alcohol oxidation by high-efficiency photocatalytic water-cracking, and belongs to the field of photocatalyst preparation and application. According to the invention, nickel sulfate hexahydrate, sodium selenite and titanium dioxide are taken as reactants, glycol is taken as a solvent and a reducing agent, and then aNiSe / TiO2 heterojunction photocatalyst is synthesized according to a one-step solvothermal method. The heterojunction photocatalyst prepared by the invention has a photocatalytic hydrogen productionperformance 9 times higher than that of pure TiO2, and shows good stability in the long-cycle operation. Furthermore, simple alcohols are taken as sacrificial agents, and chemicals of high-value fuel(hydrogen), small molecular acids, aldehydes and the like are prepared through the photocatalytic water cracking under illumination of simulated sunlight. In addition, the heterojunction photocatalystused in the invention is green and simple in preparation method, rich in material sources, low in cost and stable in activity, and combines the small molecular alcohols as the sacrificial agents, sothat economic benefits of photocatalysis and the utilization rate of absorbed light energy can be greatly improved.

The invention discloses a preparation method of a 2D / 2D g-C3N4 / ZnIn2S4 heterojunction composite photocatalyst. The preparation method includes: firstly modifying a ZnIn2S4 photocatalyst with sodium citrate to find an optimal dosage; then further optimizing the g-C3N4 photocatalyst; and performing in-situ growth of a layer of ZnIn2S4 nanosheet on the surface of a g-C3N4 nanosheet, thus obtaining the 2D / 2D g-C3N4 / ZnIn2S4 heterojunction composite photocatalyst. The preparation method provided by the invention is simple, the raw materials are easily available, and reaction conditions are moderate.The prepared g-C3N4 / ZnIn2S4 two-dimensional composite photocatalytic material has efficient photocatalytic hydrogen production activity, and the hydrogen production rate reaches 3.4mmol / h / g, which isincreased by 180% compared with the hydrogen production rate of single g-C3N4.

The invention discloses a fluorine-substituted Zn / Co porphyrin-based conjugated organic polymer as well as a preparation method thereof and application thereof. Required raw materials are wide in source, the synthesis process is easy to control, a Sonogashira coupling reaction is adopted to expand the light absorption range of a porphyrin complex to a near-infrared light region, and the transfer of photo-induced electrons between Zn and Co center metals can be accelerated, and the recombination of the electrons and holes is reduced, so that photons in an ultraviolet-visible-near-infrared lightregion are effectively utilized to realize efficient photocatalytic hydrogen production, and a good application prospect is shown in the aspect of photocatalytic hydrogen production with wide spectral response.

The invention belongs to the technical field of photocatalysis, and particularly discloses a ZnIn2S4 / MQDs composite photocatalyst as well as a preparation method and application thereof. The ZnIn2S4 / MQDs composite photocatalyst is prepared from the following components in percentage by mass: 1 to 4 percent of MXene quantum dots and 96 to 99 percent of ZnIn2S4. According to the invention, ZnIn2S4 is modified by using an electronic auxiliary agent MXene QDs, and abundant active sites are provided for hydrogen evolution reaction. The preparation method provided by the invention is simple in process, and the prepared composite photocatalyst has very high efficiency of catalytically cracking water to produce hydrogen when no noble metal is used as a cocatalyst, is high in photocatalytic activity, low in cost and pollution-free, can be recycled, and is high in application and popularization performance.

The invention relates to the technical field of composite photocatalysis, in particular to a NiCoP-g-C3N4 / CdS composite photocatalyst as well as a preparation method and application thereof. The method comprises the steps of firstly, preparing pure CdS through a solvothermal method, and preparing g-C3N4 by directly calcining urea, wherein the g-C3N4 and the CdS have proper valence band and conduction band structures; preparing a g-C3N4 / CdS heterojunction through a chemical adsorption and self-assembly method; then adding a nickel source, a cobalt source and a phosphorus source into ultrapure water according to the mass ratio of 1: 1: 5; after the mixture is fully stirred and dissolved, adding a prepared g-C3N4 / CdS composite material, carrying out uniform ultrasonic treatment, completely evaporating moisture to dryness, and finally, calcining to successfully load granular NiCoP on the surface of the g-C3N4 / CdS heterojunction. The color of the composite material is related to the doping amount of NiCoP, the color of the composite material is gradually darkened from grass green along with the increase of the doping amount of NiCoP, the prepared composite photocatalyst is applied to a hydrogen evolution experiment, the hydrogen evolution performance is excellent, the hydrogen evolution rate is more than 23 times that of pure CdS, the repeated utilization rate is high, and the composite photocatalyst has a wide application prospect in the field of photocatalysis.

The invention discloses a supported photocatalyst NiSe / Mn0.5Cd0.5S and a preparation method thereof. The supported photocatalyst is prepared by firstly synthesizing a Mn0.5Cd0.5S solid solution by using a gentle one-step hydrothermal method, and by secondly, enabling the solid solution to react with nickel sulfate hexahydrate and sodium selenite. NiSe and Mn0.5Cd0.5S are tightly combined to form heterojunctions in the composite catalyst, migration of photon-generated carriers can be facilitated, combination of photon-generated electron holes is inhibited, and the photocatalysis hydrogen production activity of the Mn0.5Cd0.5S solid solution can be remarkably improved. The novel NiSe / Mn0.5Cd0.5S photocatalyst disclosed by the invention is simple to prepare, can be massively prepared, is highin photocatalysis activity and good in stability, and has wide application prospects in clean energy development.

The invention discloses a Nb-Rh co-doped titanium dioxide nanorod photocatalyst, and a preparation method and application thereof. The photocatalyst of the invention has the following advantages: 1) the photocatalyst prepared in the invention has a one-dimensional rod structure and is effectively improved in photocatalytic hydrogen production activity compared with a common photocatalyst; 2) the preparation method of the photocatalyst is simple and can easily realize large-scale commercial production; 3) the photocatalyst can be reused, and the catalytic activity of the Nb-Rh co-doped titaniumdioxide nanorod photocatalyst is free of obvious decline after reuse 20 times or more; and 4) the Nb-Rh co-doped TiO2 nanorod photocatalyst has high catalytic activity, e.g., a Ti<0.996>Nb<0.002>Rh<0.002>O<2> nanorod photocatalyst has a hydrogen production rate of up to 7.58 mmol / g.h in photolysis of water, which is 194 times the hydrogen production rate (0.039 mmol / g.h) of TiO2 nanorods preparedunder the same conditions.

The invention discloses a preparation method of Zn-Cr-O / TiO2-nanotube (NTs) composite oxide with efficient photoelectric conversion and photocatalytic performance. The specific preparation method comprises the steps that through an electrochemical workstation, the oxide voltage and time are controlled, in an electrolyte prepared through lower alcohol, fluoride and ultrapure water, through the anodic oxidation method, the precursor is prepared, program warming and roasting are carried out, and TiO2-NTs is obtained; the TiO2-NTs is immersed in a zinc nitrate and chromic nitrate mixed solution with the quantity relative ratio being (1.0 to 7.0):1.0, the cathode deposition and electrochemical oxidation technology is adopted into TiO2-NTs loaded Zn-Cr-O composite oxide, deposition sample rotating is carried out, and the Zn-Cr-O / TiO2-NTs composite oxide with excellent photoelectric conversion and photocatalytic performance is obtained.

The invention discloses an annealing treatment method for improving photo-catalytic hydrogen production activity of a zinc sulfide material. According to the annealing treatment method, S atmosphere is provided for annealing treatment of a ZnS nanomaterial; since the ZnS nanomaterial obtained through hydrothermal synthesis contains more S vacancy defects, the ZnS material and S powder are sealed in a vacuum quartz tube by using oxy-hydrogen flame and heated to a certain temperature for annealing to fill S atoms in S vacancies, so that lattice internal defects of the material are eliminated. According to the method, the photo-catalytic hydrogen production activity of the ZnS material is greatly improved, and the method can have an important effect on actual application of the ZnS material in photocatalysis.

The invention discloses a layered stromal HTiTaO5 / CdS Pt-carrying new-typed composite catalyst and making method, which comprises the following steps: mixing K2CO3, Ta2O5 and TiO2 at chemical gauge rate; sintering to obtain the KTiTaO5 product; proceeding KTiTaO5 to obtain catalyst layered stromal HTiTaO5 through nitric ion exchange; exchanging the stromal HTiTaO5 with saturated cadmium acetate ion through pile-supported propanamine; vulcanizing the exchanged stromal HTiTaO5 in the pipe-typed furnace hydrogen sulfide atmosphere at high temperature to produce HTiTaO5 / CdS; carrying Pt through photoreduction. The invention reaches the highest hydrogen-producing rate at 144umol / h and 6.3 percent quantum efficiency at 420 nm and 1.67 percent optical conversion efficiency for all-band of visible light, which improves the product activity.

The invention relates to a Nb-Rh co-doped titanium dioxide photocatalyst, and a preparation method and application thereof. The catalyst is synthesized by doping modification of TiO2 with Nb and Rh. The Ti<1-x-y>Nb<x>Rh<y>O<2> photocatalyst synthesized through doping modification has excellent photocatalytic effect and is mainly applied to photocatalytic cracking of water and photocatalytic cracking of organic matters. The modified Ti<1-x-y>Nb<x>Rh<y>O<2> photocatalyst maintains the original chemical stability of TiO2. With the above characteristics, the photocatalyst has good application prospects in the fields of energy and environment.

The invention relates to the field of photocatalysis. The invention discloses a composite photocatalyst and a preparation method thereof. The composite catalyst is a composite photocatalyst with Ni@NiOx as a CdS promoter. The preparation method comprises the following steps: synthesizing CdS nanowires with amino groups adsorbed on the surface; preparation of Ni / CdS composite photocatalyst; preparation of Ni@NiOx / CdS composite photocatalyst: Ni@NiOx / CdS composite photocatalyst is obtained by calcining Ni / CdS composite photocatalyst at low temperature. The invention reduces the hydrogen production overpotential of Ni and improves the photocatalytic hydrogen production activity by supporting Ni on the surface of CdS through simple solvothermal reduction and forming NiOx on the surface of Ni instead of the surface of CdS by a low-temperature calcination method. The raw materials used are easy to obtain and the preparation method is simple. The material prepared by the invention is appliedto photocatalytic hydrogen production, and the photocatalytic hydrogen production efficiency of the composite sample is 104 times as high as that of pure CdS.

The invention discloses a preparation method and an application of a cadmium sulfide nanosheet and belongs to the technical field of preparation of semiconductor photocatalytic materials. The preparation method includes (1), placing cadmium salt in a small crucible, covering the small crucible with a lid, and placing the small crucible in a big crucible; (2), adding thiourea in the big crucible until the small crucible is coated with thiourea; (3), covering a lid of the big crucible, calcining the big crucible in a muffle furnace at the temperature of 300 DEG C, and holding the temperature for4 hours, naturally cooling to the room temperature after finishing the reaction, and then taking out a product; (4), grinding, cleaning and drying the product to obtain the cadmium sulfide nanosheet.As a solid precursor- cadmium salt is calcined in the atmosphere of thiourea to prepare the cadmium sulfide nanosheet, adding of any organic or inorganic solution is avoided in the preparation process; preparation conditions are mild, operation is convenient, and accordingly the preparation method is suitable for large-scale industrial production; further, the photocatalytic hydrogenation activity of the cadmium sulfide nanosheet is improved greatly.

The invention discloses a preparation method of strontium titanate with adjustable strontium vacancy and an application of strontium titanate in photocatalytic hydrogen production. Strontium titanatecrystals are prepared by a citric acid complexing method, a strontium titanate sample is obtained by calcining, strontium titanate with different strontium vacancy content is obtained by changing theuse amount of strontium acetate in the photocatalytic material provided by the invention, strontium vacancies are introduced into strontium titanate, so that the separation efficiency of photo-inducedelectrons and holes excited by the strontium titanate photocatalyst under an illumination condition is improved, the photocatalytic hydrogen production efficiency of the catalyst is improved, and thehydrogen production efficiency can be well improved when strontium titanate containing a proper amount of strontium vacancies is used for photocatalytic hydrogen production, the maximum average hydrogen production efficiency after illumination can reach 5.8202mmol / g, therefore thestrontium titanate catalyst has a potential application value for solving the problem of energy crisis and alleviatingthe lack of existing resources.

A preparation method and application of cadmium sulfide nanosheets belong to the technical field of semiconductor photocatalytic material preparation. Specific process: 1) Place the cadmium salt in a small crucible, cover the pot, and place it in a large crucible; 2) Add thiourea into the large crucible until thiourea completely covers the small crucible; 3) Put the large crucible into Cover the pot and place it in a muffle furnace for calcination. The calcination temperature is 300°C and the holding time is 4h. After the reaction is completed, it is naturally cooled to room temperature and taken out; 4) The product obtained in the previous step is ground, washed and dried. , the cadmium sulfide nanosheets can be obtained. The method is obtained by calcining the solid precursor cadmium salt in the atmosphere of thiourea in the next step, without adding any organic or inorganic solution in the preparation process, the preparation conditions are mild, the operation is simple and convenient, and it is suitable for large-scale industrial production, and the obtained cadmium sulfide nanosheets The photocatalytic hydrogen production activity was significantly improved.

The invention relates to a ZnIn2S4 photocatalyst synergistically modified by a hole assistant Ti(IV) and an electron assistant MXene QDs, belongs to the technical field of photocatalysis, and particularly discloses a ZIS / Ti / MQDs composite photocatalyst, a preparation method and application thereof. The ZIS / Ti / MQDs composite photocatalyst comprises, by mass, 1%-4% of MXene quantum dots; and 96%-99% of a ZIS / Ti mixture; the ZIS / Ti mixture is ZnIn2S4 doped with Ti(IV), and the doping mass percent of the Ti(IV) is 0.2%. According to the invention, ZnIn2S4 is synergistically modified by utilizing the hole assistant Ti(IV) and the electron assistant MXene QDs, and abundant active sites are provided for hydrogen evolution reaction. The preparation method provided by the invention is simple in process, and the prepared composite photocatalyst has very high efficiency of catalytically cracking water to produce hydrogen when no noble metal is used as a cocatalyst, is high in photocatalytic activity, low in cost and pollution-free, can be recycled, and is high in application and popularization performance.

The invention discloses a carbon dot / carbon nitride / titanium dioxide composite material, which is composed of three-phase carbon dots, graphene-like carbon nitride and titanium dioxide; among them, carbon nitride has a large surface area, which is just right Provides a depositable space for titanium dioxide nanosheets to prevent titanium dioxide from agglomerating. At the same time, the narrow bandgap width of carbon nitride can increase the photoresponse range. Moreover, the present invention also uses the unique electron transfer ability of carbon dots to further suppress The recombination of photogenerated electron pairs increases the photocatalytic performance. In addition, the preparation method of the present invention has mild process conditions, low cost, is suitable for large-scale production, and has broad application prospects.

The invention discloses a nickel carbonate-supported titanium dioxide ultraviolet light catalyst and a preparation method thereof. The light catalyst comprises the following raw materials in parts by weight: 1 part of titanium dioxide, 0.2-0.5 part of inorganic carbonate and 0.001-0.4 part of inorganic nickel salt. The method comprises the following steps: dissolving inorganic carbonate into water to obtain an inorganic carbonate water solution of which the molar concentration is 0.1-1.0mmol / L; dispersing titanium dioxide into the inorganic carbonate water solution to obtain a suspension; and finally, slowly adding the inorganic nickel salt into the suspension, stirring evenly, washing and standing, filtering by using filter paper, and drying in vacuum at 60-100 DEG C for 4-8 hours so as to obtain the nickel carbonate-supported titanium dioxide ultraviolet light catalyst. Compared with a traditional supporting technology that a supporter of a transition metal oxide needs to be calcined by using electric energy, the method does not have preparation cost and is free of electric energy] consumption; and the cost for preparing the light catalyst is increased by less than 1 yuan per 500g on the basis of the cost of titanium dioxide.

The invention discloses a dibenzo fused dinaphthyl polymer photocatalyst for hydrogen production by photocatalytic decomposition of water and a preparation method thereof, the photocatalyst is prepared by a simple binary or ternary copolymerized Suzuki coupling reaction, and the construction unit of the photocatalyst comprises dibenzo fused dinaphthyl and dibenzothiophene sulfone. The dibenzo fused dinaphthyl monomer and the dibenzothiophene sulfuryl monomer for polymerization have the same or different polymerizable functional groups, and can be subjected to Suzuki coupling reaction. The polymer photocatalyst has the characteristics of high photocatalytic hydrogen production activity, high apparent quantum efficiency and continuous and adjustable structure and composition, is simple in preparation process, high in yield and stable in performance, can release hydrogen under sunlight, and can be used in the field of photocatalytic hydrogen production.