31results about How to "Improve photocatalytic hydrogen production efficiency" patented technology

The invention relates to a Nickel single-active site graphite-phase carbon Nitride-based photocatalytic material as well as a preparation method and application thereof, in the photocatalytic material, Ni is dispersed in a g-C3N4 framework in a single-atom-level degree to form active sites, and the molar content of the Ni is 1-5%. the nickel single-active site graphite-phase carbon nitride-based photocatalytic material has a large specific surface area, is good in dispersion in an aqueous solution, and can effectively inhibit the recombination of photo-generated carriers, the reaction activitysites of the surface of the g-C3N4 are increased, the photocatalytic hydrogen production efficiency can be remarkably improved, and the photocatalytic reaction activity of the g-C3N4 can be improved.

The invention discloses a quantum dot catalyst doped with metal ions. The catalyst includes a light-harvesting unit and a catalyzing unit, wherein the light-harvesting unit includes one, two or several kinds of quantum dots, and the catalyzing unit comprises the metal ions doped in the quantum dots. The metal ions are dispersed on the quantum dots in the following one or several manners that: (1) the metal ions are adhered to the surface of the quantum dots; (2) the metal ions are uniformly dispersed in the quantum dots; (3) the metal ions are disposed in the quantum dots in a gradient alloy way; (4) the metal ions are merely disposed on cores of core-shell quantum dots; (5) the metal ions are merely disposed on shells of the core-shell quantum dots; (6) both the cores and shells of the core-shell quantum dots are doped with the metal ions. The invention further discloses a photocatalytic hydrogen production system of doped quantum dots. The system has high efficiency of a quantum-dot-catalyst photocatalytic hydrogen production system and simplicity of a single quantum-dot photocatalytic hydrogen production system. The system can conveniently combine with an oxygen production half-reaction to totally decompose water.

A photocatalytic decomposing water hydrogen production material CdS/Sr1.6Zn0.4Nb2O7 is a catalyst having a heterojunction structure formed by loading CdS on Sr1.6Zn0.4Nb2O7. The inventive catalyst is prepared by a hydrothermal method through sol gel. When a molar ratio of the CdS and the Sr1.6Zn0.4Nb2O7 is 3:7, the expression is 30%CdS/Sr1.6Zn0.4Nb2O7, and the catalytic effect of the material is best. Under the illumination of a 300 watt xenon lamp, Na2S/Na2SO3 is taken as a sacrifice reagent, the inventive material 30%CdS/Sr1.6Zn0.4Nb2O7 photocatalyzes and decomposes the water to produce the hydrogen without a co-catalyst of noble metal, and the efficiency is 645.7 mu mol.h<-1>.g<-1>. The photocatalytic decomposing water hydrogen production material of the invention has the advantages that: 1 the inventive catalyst is directly synthesized by the hydrothermal method through sol gel, the operation is simple, the production cost is low, the synthetic yield is higher, the purity is high and the repeatability is good, and the inventive catalyst is suitable for the demand of magnification production; 2, the inventive catalyst is good in the stability and is easy to reuse; and 3, the inventive catalyst has higher photocatalytic hydrogen production efficiency.

The invention relates to a titanium dioxide-platinum-tricobalt tetraoxide tri-element composite photocatalytic material and a preparation method thereof.Titanium dioxide nanosheets with exposed faces {001} and {101} are used as a carrier, platinum and tricobalt tetraoxide nanoparticles are used as a co-catalyst, the platinum particles are loaded on the faces {101} of the titanium dioxide nanosheets, and the tricobalt tetraoxide nanoparticles are loaded on the faces {001} of the titanium dioxide nanosheets.Photocatalytic decomposing water of the material is high in hydrogen generating efficiency, and the co-catalyst and titanium dioxide are combined closely, so that the material is high in stability after long-time use and the problem that photocatalytic efficiency is lowered caused by the fact that photocatalyst electron holes are highly prone to compositing in the prior art is solved effectively.

The invention relates to an adsorption photocatalytic hydrogel material and an application thereof in synergistic photocatalytic sewage hydrogen generation capable of reversing heavy metal pollution. The adsorption photocatalytic hydrogel material comprises a photocatalytic nano material and a porous transparent matrix for loading the photocatalytic nano material. The porous transparent matrix is prepared from a polysaccharide polymer material, which carry out crosslinking easily to form hydrogel. The polysaccharide hydrogel is rich in functional groups such as -OH, -NH3, and the like, can absorb heavy metal ions, and reduces the concentration of heavy metal ions in sewage.

The invention belongs to the technical field of materials, and provides a preparation method and application of a modified material based on titanium dioxide, which comprises the following steps: dissolving a certain amount of boric acid and rhodium chloride trihydrate in water containing nitric acid and alcohol to obtain a solution A; dropwise adding isopropyl titanate into the ethanol solution at the temperature of 0-4 DEG C to obtain a solution B; slowly dropwise adding the solution A into the solution B to obtain titanium dioxide sol; aging the titanium dioxide sol at room temperature, andperforming drying to obtain xerogel; and finally, grinding the dry gel into powder, and calcining the powder in air for 4 hours to obtain the boron-rhodium co-doped titanium dioxide, namely the titanium dioxide-based modified material. The material is used for photocatalytic hydrogen production, and the catalytic hydrogen production efficiency is effectively improved. The boron-rhodium co-doped titanium dioxide is prepared by adopting a one-pot sol-gel method, the absorption bandwidth of the titanium dioxide can be regulated and controlled by adjusting the rhodium doping proportion, and the light absorption and carrier separation efficiency is improved.

The invention relates to a graphite phase carbon nitride foam photocatalytic material and a preparation method thereof. The preparation method includes adding 5-14 parts by mass of graphite phase carbon nitride to 100 parts by mass of deionized water, mixing, further adding 1.7-2.0 parts by mass of sodium dodecyl sulfate, 1.7-2.0 parts by mass of dodecyl alcohol and 1.7-2.0 parts by mass of resingum and stirring at 40-60 DEG C and 100-200 r/min for 10-20 minutes to obtain a mixed solution; stirring the mixed solution at 1500-2000 r/min for 15-20 min, then adding 5-14 parts by mass of binder and continuing stirring for 5-10 min to obtain graphite phase carbon nitride foam slurry; molding the graphite phase carbon nitride foam slurry by casting, freeze drying for 6-12 hours, and drying at 80-100 DEG C for 18-24 hours to obtain the graphite phase carbon nitride foam photocatalytic material. The preparation method has simple process and low cost. The prepared graphite phase carbon nitridefoam photocatalytic material has high photocatalytic hydrogen production efficiency.

The invention discloses a silicon carbide-based double-additive hydrogen producing photocatalyst and a preparation method thereof. The preparation method comprises the following steps of a, performingpretreatment on silicon carbide; b, by taking molybdenum disulfide as a raw material, preparing 8 wt% molybdenum disulfide suspension liquid of a whole hydrothermal reaction system; c, putting 100 mLof 8 wt% molybdenum disulfide suspension liquid in a beaker, sequentially adding silicon carbide (SiC), graphene oxide (GO) and two drops of 1-butyl-3-methylimidazolium hexafluorophosphate ionic liquid, and performing ultrasonic stirring to enable the components to be uniformly mixed; and d, transferring the mixture into a high-temperature reaction kettle, performing reaction for 20 h at the temperature of 220 DEG C, then performing centrifugal washing until a pH value is 7, putting the product in a vacuum drying tank, performing vacuum drying for later use, and performing hydro-thermal synthesis to obtain the silicon carbide-based double-additive hydrogen producing photocatalyst. According to the preparation method provided by the invention, for the silicon carbide-based double-additivehydrogen producing photocatalyst prepared by utilizing the synergistic effect of GO-molybdenum disulfide (MoS2) double-additive catalyst, the performance of photocatalytically decomposing water with visible light to produce hydrogen is improved, and a certain foundation can be laid for subsequent efficient application of a visible light catalyst.

The invention provides a graphene quantum dot modified manganese oxide/titanium oxide nanotube array material and a preparation method and application thereof, and belongs to the field of photocatalysis of film materials. A titanium dioxide material is composited and modified through graphene quantum dots and manganese oxide; compared with titanium dioxide materials, the titanium dioxide materialmodified with quantum dots have improved electrochemical properties; the compositing with manganese oxide enables absorbing boundary of titanium dioxide to be widened, forbidden band width of titaniumdioxide can be evidently decreased, the absorbing boundary is extended, titanium dioxide can utilize visible light more efficiently, compositing of photo-induced electrons and holes is inhibited, photocatalytic activity of titanium dioxide is improved, and hydrogen can be produced by photoelectric catalysis of titanium dioxide more efficiently; in addition, reduced graphene oxide and titanium sheeting are nontoxic and pollution free, the cost is low, and the preparation method has the advantages of simplicity, convenience and high speed; the morphology and properties are controlled by controlling reaction voltage and time and water bath reaction time, and the operation is simple.

The invention relates to a material CdS/Ba0.4Sr0.6TiO3 for producing hydrogen by photocatalytically decomposing water, which is a heterostructure catalyst formed by supporting CdS onto Ba0.4Sr0.6TiO3. The catalyst is prepared by a one-step hydrothermal process. When the mole ratio of the CdS to the Ba0.4Sr0.6TiO3 is 0.4:1, the expression is 40%CdS/Ba0.4Sr0.6TiO3, and the material has the optimal catalytic effect. Under simulated sunlight, by using Na2S/Na2SO3 as a sacrifice reagent, the hydrogen production efficiency by photocatalytically decomposing water of the 40%CdS/Ba0.4Sr0.6TiO3 is up to 1268.4 mu mol.h<-1>.g<-1> under the condition of no noble metal for cocatalysis. The one-step hydrothermal process is directly used for synthesizing the catalyst, is simple to operate, has the advantages of low production cost, higher synthesis yield, higher purity and favorable repetitiveness, and is suitable for the requirement for scale-up production; the catalyst has high stability and is convenient for reutilization; and the catalyst has very high photocatalytic hydrogen production ratio under simulated sunlight.

The invention discloses a preparation method and application of a molybdenum disulfide/boron-doped graphite-phase carbon nitride composite visible light photocatalyst, wherein boron-doped graphite-phase carbon nitride is prepared by reacting and sintering urea and sodium tetraphenylborate (PH4BNa), and molybdenum disulfide is prepared by a hydrothermal method. According to the invention, boron-doped graphite-phase carbon nitride photocatalyst is compounded with proper molybdenum disulfide to prepare an efficient catalyst, wherein the boron-doped graphite-phase carbon nitride has high specificsurface area and chemical stability, and molybdenum disulfide can accelerate separation of photo-excited electron hole pairs in boron-doped graphite-phase carbon nitride, so that excellent catalytic activity is achieved, the photocatalytic hydrogen production efficiency of the molybdenum disulfide/boron-doped graphite-phase carbon nitride photocatalyst is improved, and the photocatalyst has potential application value in the aspect of coping with energy crisis.