155results about How to "Product yield is high" patented technology

The invention discloses a preparation method of a stannic oxide nanocrystalline loaded tin disulfide nanosheet composite nanomaterial. The method comprises the following steps that S1, a tin disulfide nanosheet is prepared, wherein L-cysteine and stannic chloride are dissolved in water and are mixed evenly, light yellow sediment is obtained after a hydrothermal reaction, rinsing, centrifugal separation and drying are carried out, and the SnS2 nanosheet is obtained; S2, a composite material is prepared, wherein stannic chloride and vitamin C are dissolved in water, the SnS2 nanosheet prepared in the S1 is dispersed in the solution, then NaHCO3 is added, even mixing is carried out, a microwave reaction is carried out under the backflow condition, cooling, rinsing, centrifugal separation and drying are carried out, and the composite nanomaterial SnO2 / SnS2 is obtained. The molar ratio of the L-cysteine to the stannic chloride added in the S1 is 6-8:1, and the molar ratio of the stannic chloride added in the S2 to the SnS2 nanosheet is 1-5:1. According to the prepared SnO2 / SnS2 composite material, SnO2 nanocrystalline is evenly dispersed and firmly loaded on the SnS2 nanosheet, the caking phenomenon of the SnO2 nanocrystalline is avoided, and the obviously-enhanced catalytic property is shown.

The invention relates to a method for synthesizing quinazolino indazole derivatives under acidic condition, which comprises the following steps: under existence of a catalyst and an oxidizing agent, an intramolecular dehydrogenation coupling reaction of 2-aryl-3-aryl amino quinazolinone derivatives is produced in an acidic organic solvent so as to obtain the quinazolino indazole derivatives with diversified structures. The method is characterized in that under the synergistic effect of the catalyst, the oxidizing agent and the acidic organic solvent, a reaction for efficiently synthesizing the quinazolino indazole derivatives by a one-pot method is achieved, and the method has the advantages of high efficiency, environmental friendliness, high yield and purity and the like, and has good research value and application prospect.

The invention relates to a MoS2 / Ni3S2 electrode material as well as a preparation method and application thereof, which belongs to the technical field of environmental protection and energy of hydrogen production by virtue of electric decomposition of water. The application of different sulfur sources is verified to have great influence for the morphology and performance of a catalyst; and by virtue of comparison, the MoS2 / Ni3S2 electrode synthesized by using thioacetamide as a sulfur source has optimum morphology, performance and reaction active site, the over-potential for the reaction can be greatly reduced, and the energy loss in the electrochemical hydrogen production process can be reduced. Meanwhile, the synthetic method is simple, and the foam nickel self-supported MoS2 / Ni3S2 electrode can be synthesized by adopting a one-step hydrothermal method, so that the industrialized production and actual application value is high.

The invention relates to a gallium nitride / zinc oxide solid solution with a high zinc content and a preparation method thereof. The mass content of zinc oxide is greater than 50% and less than or equal to 80%. The bimetal hydrate precursor of Zn / Ga / CO3 is prepared firstly, and then the precursor is nitridized to obtain the gallium nitride / zinc oxide solid solution with a high zinc content. The preparation method provided by the invention has simplicity and high preparation yield, and the prepared product has a high content of zinc oxide and adjustable contents of components.

The invention relates to a preparation method of a temperature and pH sensitive shell cross-linked polymeric micelle, characterized by synthesizing a temperature and pH sensitive diblock copolymer by reversible addition-fragmentation chain transfer (RAFT) polymerization, and then using small-molecule dialdehyde or diacid to carry out part crosslinking on the shell structure of a self-assembled polymeric micelle. The method has the characteristics of simpleness, convenience, high preparation yield, no environmental pollution, and the like. The prepared diblock copolymer has the advantages of strong functionality and narrow molecular weight distribution. By using small-molecule cross-linking agent to carry out part crosslinking on the micelle shell structure, under the precondition of guaranteeing the stability of the polymeric micelle, the preparation method has the characteristics of strong feasibility and simple operation, and can reutilize micelles, etc. The obtained temperature and pH sensitive shell cross-linked polymeric micelle has excellent drug loading performance, can rapidly and efficiently adsorb readily degradable or indissoluble drugs under different concentration conditions, is a new generation high performance drug loaded product, and can be applied in the medicine fields of in vivo transfer, gene vectors, and the like.

The invention discloses a method and system for recovering waste water generated in carbocisteine production. The system comprises a bipolar membrane electro-dialysis desalination system and a recovering system; the recovering system comprises an acid concentrating and recovering system, a base concentrating and recovering system and a carbocisteine concentrating and recovering system. With the adoption of the system, salts in the waste water generated in carbocisteine production can be converted into corresponding acid and base so as to be removed; the obtained acid and base can be directly used in the carbocisteine production process or be used in the carbocisteine production process after an advanced treatment; the carbocisteine in the waste water is further recovered by using a carbocisteine concentrating crystallizing system. By treating the waste water generated in the carbocisteine production by using the method, organism pollution, salt pollution and ammonia nitrogen pollution are avoided; in addition, the recovered acid and base can be reused in the carbocisteine production process to realize zero emission; by using the recovered carbocisteine, the carbocisteine yield is increased and the cost of the method provided by the invention can be further reduced.

The invention relates to a preparation method of 6-bromine-2-pyridine methyl formate. The preparation method comprises the step of catalyzing esterification reaction of 6-bromine-2-pyridine carboxylic acid by taking p-toluenesulfonic acid as a catalyst, to be specific, heating and fluxing absolute methanol, the 6-bromine-2-pyridine carboxylic acid and the p-toluenesulfonic acid for 2-8 hours under stirring, cooling to a room temperature after reaction is ended, rotary drying a reaction system, dissolving solids in an organic solvent, washing, drying, filtering, concentrating, recrystallizing a concentrated product by a mixed solvent to obtain the 6-bromine-2-pyridine methyl formate, wherein a preferable molar ratio of the 6-bromine-2-pyridine carboxylic acid and the p-toluenesulfonic acid is 1: (0.1-0.16). According to one embodiment of the invention, the 6-bromine-2-pyridine carboxylic acid is obtained through diazotization, bromination and oxidation of 6-amino-2-methylpyridine. The preparation method is few in side reaction and simple in aftertreatment and is suitable for industrial production; and the product is easy to separate and has high yield, high purity and good quality.

The invention discloses a method for preparing lactide by a catalytic method under reduced pressure, which is characterized by comprising the following steps: firstly, removing free water in lactic acid at a temperature is 75-90 DEG C and at a vacuum degree of 0.080-0.090 MPa for 1-2 hours; secondly, adding a catalyst and a surfactant, wherein the catalyst consists of zinc oxide with a reactant mass percentage of 0.5-1 percent and stannous octoate with a reactant volume ratio of 0.5-1 percent, the surfactant is Tween 80 with a reactant volume ratio of 0.5-1 percent or sodium dodecyl sulfate with a reactant mass percentage of 0.5-1 percent ; thirdly, at a vacuum degree of 0.080-0.090 MPa and a temperature of 125-135 DEG C, removing combined water and reacting for 5 hours; and fourthly, agitating and raising the temperature to 165-200 DEG C, distilling and collecting the lactide with a crude production rate of 83-91 percent. The method has the beneficial effects that the distillation temperature of the lactide in the lactide preparation process can be reduced, the energy consumption is reduced, the by-product quantity generated at high temperature is reduced, the preparation production rate of the lactide is further improved, and the production cost is reduced.

The invention relates to the field of organic second-order nonlinear optical materials and especially relates to an organic second-order nonlinear optical chromophore which has a D-pi-A structure and utilizes julolidine or its derivative as an electron donor, a thiophene ring or a cyclic polyene structure as a conjugate electron bridge and tricyano-dihydro furan or trifluoro-substituted tricyano-dihydro furan as an electron acceptor, and its synthesis method and use. Through combination of the used electron donor, conjugate pi electron bridge and electron acceptor, the organic second-order nonlinear optical chromophore can improve an intramolecular electron transfer capability and improve intermolecular steric hindrance. The organic second-order nonlinear optical chromophore can effectively improve a chromophore molecule first-order hyperpolarization rate (beta) and can effectively reduce intermolecular interaction. The organic second-order nonlinear optical chromophore adopted with amorphous polycarbonate can be used for preparation of a polarized polymer film. The polarized polymer film can be used as a material in the optical signal modulation field. The organic second-order nonlinear optical chromophore has a structure shown in the following description.

The invention discloses a drain plate for preparing electronic grade spun yarns. Novel drain nozzle distribution is adopted on bottom plates, so that the production efficiency is greatly improved at the same time of ensuring that the quality of products does not decline. The bottom plates of the drain plate are divided into five areas in totally same size, shape and arrangement mode, the drain nozzles of each area are arranged in a mode of fillet parallelogram array consisting of 12 columns and 17 rows, and the fillet parallelogram array is formed by respectively removing one drain nozzle on four corners from the parallelogram array consisting of the drain nozzles and provided with 200 drain nozzles. The drain nozzle fillet matrix of the novel drain plate is more symmetrical compared with the drain nozzle fillet matrix of 13 columns and 16 rows of an 800-pore drain plate, so that the glass silk distribution is more uniform in the subsequent process and the product yield is increased at the same time of ensuring the product quality. Meanwhile, the subsequent process of drain plate production is correspondingly improved.

The invention discloses a preparation method of cerium-doped yttrium aluminum garnet nano / micro-scale spherical fluorescent powder. The material is Y3-xCexAl5O12, wherein x is greater than 0 and smaller than or equal to 0.3. The preparation method provided by the invention is a co-precipitation-solvothermal method and comprises the following steps: firstly, preparing a YAG:Ce<3+> or a YAG precursor by using a co-precipitation method; secondly, carrying out solvothermal reaction in a reaction kettle, with ethylenediamine or an ethylenediamine-alcoholic solution as a solvent, reacting at the temperature of 260 to 290DEG C for 12 to 48 hours; and dissolving and recrystallizing to generate single-phase Y3-xCexAl5O12 fluorescent powder with high yield, high repeatability, higher illumination brightness and high crystallization degree. Without subsequent high-temperature roasting or atmosphere reduction, particle agglomeration caused by calcining is effectively reduced. The preparation method has the advantages that control over size and morphology of materials is realized at relatively-low temperature and pressure; the size of a powder material can be adjusted and controlled within therange of 0.1 to 2.0 [mu]m according to the demand; the process is simple, conditions are easily to control and no special expensive equipment is needed; the materials are stable in performance, regular in spherical morphology and high in dispersity; and a selected reagent is wide in source and easy to obtain.

The invention discloses a method for preparing a spinnable polysiloxane ceramic precursor for SiC fibers, which comprises the following steps of: (1) adding chlorosilane, chlorinated siloxane and dimethylbenzene into a neck flask according to a certain mass ratio; (2) vacuumizing the neck flask, introducing N2 for protection, slowly raising the temperature to 70-90DEG C, keeping constant temperature, simultaneously performing mechanical stirring, dripping aqueous solution of an alkaline substance, and continuously stirring for reaction for 6 to 24 hours at constant temperature under the protection of the N2; (3) standing reaction liquid to separate out water and impurities of the lower layer, and taking polysiloxane dimethylbenzene solution of the upper layer out; and (4) distilling the polysiloxane dimethylbenzene solution of the upper layer under reduced pressure to remove a dimethylbenzene solvent. The compound raw materials are mature industrial materials, and are wide in sources; the reaction process is easy to control, the preparation yield is high, and the product purity is high; and the prepared polysiloxane ceramic precursor is low in cost, higher in ceramic yield and good spinnability.

The invention provides a preparation method of hydrogen chloride oxidation catalyst. The preparation method comprises the following steps: adding a powder carrier into a ruthenium precursor aqueous solution, sufficiently stirring, dropwise adding into a hydrogen peroxide solution, uniformly mixing, heating, adjusting the pH value of the solution by utilizing alkali, then performing the solid-liquid separation, drying the separated solids, and obtaining the hydrogen chloride oxidation catalyst. The hydrogen chloride oxidation catalyst prepared by the invention can solve the defects of the existing hydrogen chloride oxidation catalyst that the preparation method is high in energy consumption, high in water consumption, complex in procedures, unlikely in industrialized mass preparation, low utilization efficiency of the precious metal ruthenium and the like. The preparation method of the hydrogen chloride oxidation catalyst is fewer in process procedures, small in water consumption, low in energy consumption, short in period and high in yield.

The invention provides a light emitting diode chip. The light emitting diode chip includes: a first conductive type semiconductor layer disposed on a substrate; a mesa disposed on the first conductive type semiconductor layer and including an active layer and a second conductive type semiconductor layer; an insulation layer covering the first conductive type semiconductor layer and the mesa, the insulation layer including at least one first opening exposing the first conductive type semiconductor layer and a second opening disposed on the mesa; a first pad electrode disposed on the insulation layer and electrically connected to the first conductive type semiconductor layer through the first opening; and a second pad electrode disposed on the insulation layer and electrically connected to the second conductive type semiconductor layer through the second opening. The first opening of the insulation layer includes a first region covered by the first pad electrode and a second region exposed outside the first pad electrode.

The invention provides a preparation method of nitrogen-doped graphene for a cathode of a lithium ion battery. The method comprises three processes: preparing graphene oxide, restoring graphene oxide, and preparing the nitrogen-doped graphene. The nitrogen-doped graphene is prepared by the following steps: restoring the graphene oxide into prepared graphene; putting into a vacuum tube furnace; and carrying out high-temperature annealing in an ammonia gas at 500-700 DEG C. The prepared nitrogen-doped graphene is annealed in a high-temperature environment until the nitrogen doping amount reaches the maximal value, thus the electronic structure of the graphene is changed; the density of a free carrier of the graphene is improved; and the conductive property, the stability, the first charge-discharge efficiency and the reversible capacity of the graphene are further improved.

The invention provides an axial chiral imidazole salt compound and a preparation method thereof. The structural formula of the axial chiral imidazole salt compound is that a binaphthol derivative and halogen reacts firstly to obtain a intermediate product which is coupled with o-phenylenediamine to obtain a single substituted axial chiral o-phenylenediamine compound and a axial chiral o-phenylenediamine compound with symmetrical C2. The single substituted axial chiral o-phenylenediamine compound and a heterocyclic aromatic halogenated compound or an aryl trifluoroacetic acid ester compound react to obtain an intermediate product, and the intermediate product and ortho-acid trialkyl ester react to obtain the axial chiral imidazole salt compound with R3 which is aryl. The single substituted axial chiral o-phenylenediamine compound and the ortho-acid trialkyl ester react to obtain a intermediate product, the intermediate product and a halogenated alkyl compound react to obtain the axial chiral imidazole salt compound with R3 which is alkyl. The axial chiral imidazole salt compound preparation method is high in synthesis yield, raw materials are cheap and easy to obtain, and the chiral center of the obtained axial chiral imidazole salt compound is close to a reaction point, thereby being favorable for obtaining high asymmetrical selective results.

The present invention relates to the field of medicine preparation, in the concrete, it relates to a show-released fibre preparation of water-soluble anti-cancer medicine for body implantation and its preparation method. It is characterized by that the fibre carrier is oil-soluble biological degradable material. and the medicine is water-soluble anticancer medicine, its medicine content is up to 15-50%.

The invention relates to a high-activity silver chloride convex crystal and a preparation method thereof. The crystal has a convex bent crystal face. The preparation method comprises the following steps of: dissolving a chloric ionic solution to deionized water, fully stirring for 2-4h at a room temperature, then adding silver nitride to the stirred solution, stirring for 30-60min so that the solution is uniformly mixed, putting the mixed solution into a high pressure autoclave with a polytetrafluoroethylene liner, reacting for 1-8h at 120-160 DEG C, and then cooling, separating and drying to obtain the high-activity silver chloride convex crystal. In the invention, the synthesis method and the experimental steps are simple, the preparation yield is high, and the mass production can be achieved; the synthesized silver chloride convex crystal has the convex bent crystal face and higher surface activity; and a photocatalyst prepared from the silver chloride convex crystal has strong absorbability in a visible region and stronger photocatalysis activity.

The invention discloses a water-retaining agent prepared from excess sludge, and a preparation method and a using method thereof, and belongs to the technical field of excess sludge treatment. Organicmatters contained in the excess sludge, such as proteins and polysaccharides, can be degraded by using magnetic magnesium-aluminum hydrotalcite, the ultrasonic action and an electron beam irradiationtreatment technology, and degraded polysaccharide molecules and degraded protein molecules undergo freezing, drying, heat treatment and dissolution processes under the action of hydrogen bonds, hydrophobicity, static electricity and the like to form an amphiphilic compound; and the amphiphilic compound undergoes a self-assembling reaction in a water phase to obtain a stable nanogel which can be used as the water-retaining agent. The resourceful treatment of the excess sludge is realized, the water-deficient and nutrient-deficient conditions of sandy soil can be improved, the ecological environment is restored, and the prepared water-retaining agent does not cause heavy metal or microbial pollution to soil after long-term use, does not cause hardening of soil or deterioration of physicochemical properties, and can be applied safely.

The invention discloses a new method for preparing cytidine. The method adopts the acyl-protected carbohydrate and acyl-protected cytosine as reactants and the acid or meta-acid ionic liquid as a catalyst, and comprises the following steps of: reacting at a temperature of (-5)-55 DEG C in a solvent for 5-20 hours to obtain a corresponding acyl-protected cytidine derivative; and saponifying to remove the protecting group to obtain cytidine. The new method disclosed by the invention has the advantages that: the catalyst has a wide source and is easily available; and the reaction conditions are mild, the operation is convenient, the yield is relatively high, the pollution is little, and the method can be applied to large-scale production.

The invention relates to a method for synthesizing N-phenyl indazole [3,2-b] quinazoline-7(5H)-ketone derivatives. According to the synthesizing method, 2-aminobenzoyl hydrazide compounds are reacted with triethyl orthobenzoate compounds in organic solvents in the presence of catalysts and oxidants to obtain the N-phenyl indazole [3,2-b] quinazoline-7(5H)-ketone derivatives. Through specific combination and / or selection of the catalysts and the oxidants, relatively high product yield and purity are gained, and the reaction substrates are widened, so that the method has good application prospect and research value.

The invention provides a banana tree paper making process, a pulp storage technology and a wastewater treatment technology with a soft chemistry method; the process comprises raw material collection, compression and cutting, crashing and fluffing, desliting, washing, blenching, jordaning, grinding, degumming or paper making; the pulp storage technology is as follows: a small amount of preservative is added into thick pulp to receive tumble-dry treatment; the paper making wastewater treatment is as follows: waste water and impurity removal; and the wastewater can be purified and reused. The method has the advantages of high efficiency and quickness, low raw material consumption, high yield, strong operability, high yield and good quality of paper product; the raw materials can be stored for a long time, stable supplied, nearly have no pollution to the environment, and have obvious economic benefit and environment benefit.

The invention discloses a method for preparing drug-carrying nanoparticles of a core-shell structure. The method comprises two parts, namely manufacture of a capillary micro-fluidic chip and preparation of nanoparticles. The invention firstly provides a micro-fluidic chip prepared from polydimethylsiloxane (PDMS) as the material for replacing the traditional coaxial syringe needle, taxol-carryingnanoparticles of the core / shell structure having the uniform particle size and narrow particle size distribution are prepared by combining with the coaxial electrostatic spraying method, the feasibility of the micro-fluidic chip for preparing drug-carrying nanoparticles is proved, and the problems that the nanoparticles prepared by the traditional method have the sudden release phenomenon and thePDMS array transmitter is not resistant to tetrahydrofuran, chloroform, acetone or other organic solvents are solved. Moreover, preparation of multilayer and composite structure nanoparticles can berealized.

The invention relates to the technical field of organic synthesis, specifically to a synthetic method of antistatic heat-conducting silicone oil. The synthetic method of the antistatic heat-conductingsilicone oil comprises the following steps: (1) carrying out a reaction among diisocyanate, polyether glycol and dimethyl cyclosiloxane at a temperature of 60-90 DEG C for 0.5-3 hours to obtain modified dimethyl cyclosiloxane; (2) adding rare earth oxides, a silane coupling agent, an end-capping reagent and a catalyst into the modified dimethyl cyclosiloxane, performing uniform ultrasonic dispersion, introducing nitrogen for 10-15 minutes, performing in-situ ring opening polymerization at a temperature of 90-150 DEG C for 2-24 hours, and carrying out a decomposition reaction at a temperatureof 130-150 DEG C for 1-4 hours so as to obtain modified silicone oil; (3) uniformly mixing the modified silicone oil and ionic liquid, thereby obtaining the antistatic heat-conducting silicone oil. The antistatic heat-conducting silicone oil disclosed by the invention has excellent antistatic property and excellent thermal conductivity.

The invention discloses a phenothiazine compound and a preparation method and application thereof. The phenothiazine compound is connected with a phenanthro[9,10-d]imidazole at a 3-position, the chemical structural formula of the phenothiazine compound is shown as a formula I, wherein R represents C1-C20 alkyls. By adding sodium hydroxide into a 2-methoxyl phenothiazine and halogenated alkane solution to prepare an intermediate 1 and introducing an aldehyde group, an intermediate 2 is obtained, the intermediate 2 is added into an anhydrous dichloromethane solution of anhydrous aluminum trichloride to obtain an intermediate 3, the intermediate 3 and phenanthrenequinone are dissolved in glacial acetic acid, and anhydrous ammonium acetate is added to obtain a target product through reaction.The compound can be used as a fluorescent probe to identify phosgene. The compound is stable in structure, simple and easy to obtain as a fluorescent probe and high in preparation yield, and has a certain application value.

The invention discloses a photosensitizer containing a diazo group, a diazo positive photoresist composition for a liquid crystal display (LCD) and preparation methods of the photosensitizer and the photoresist composition. The curcumin photosensitizer containing the diazo group is a compound with the structure shown in formula I described in the specification; the photoresist composition comprises film-forming resin, the curcumin photosensitizer containing the diazo group, and an organic solvent. The curcumin photosensitizer containing the diazo group has the molecular weight of 394; compared with the existing diazo naphthoquinone photosensitizer formed by carrying out esterification on esterification parent and diazo naphthoquinone sulfonyl chloride, the curcumin photosensitizer containing the diazo group is higher in resolution ratio and small in molecular weight, enables the photoresist removing process to be easy, and is less in residue. Furthermore, the curcumin photosensitizer is high in preparation yield and good in heat stability. The positive photoresist which is used for an LCD thin film transistor (TFT) and is good in storage stability and high in resolution ratio can be formed by combining the curcumin photosensitizer and the traditional film-forming resin, so that the problems that the existing diazo naphthoquinone system LCD photoresist is difficult to refine, poor in storage stability and lower in resolution ratio can be solved. The following is the formula I (in the specification).

The invention belongs to the technical filed chemical engineering and new materials, and concretely relates to a preparation method of a temperature and pH sensitive organic / inorganic hybrid material POSS-PDMAEMA. The method comprises the following steps: synthesizing polydimethylaminoethyl methacrylate through adopting a reversible addition-fragmentation chain transfer polymerization technology, and reacting polydimethylaminoethyl methacrylate with octavinyl POSS through a thiol-ene click chemical reaction to generate the organic / inorganic hybrid material POSS-PDMAEMA. In an aqueous solution, the POSS-PDMAEMA self-assembles with the change of the temperature and the pH value and forms micelle. The method has the characteristics of simplicity, convenience, high preparation yield and no pollution to environment, and the prepared organic / inorganic hybrid material POSS-PDMAEMA has temperature and pH sensitivity, is a new-generation high-performance intelligent material product, and can be applied to medicinal fields of organic dye adsorption, heavy metal adsorption and in vivo delivery of insoluble anticancer medicines.

The invention discloses a clean production method of a co-precipitation process positive material carbonate precursor. The method mainly comprises the following steps: (1) respectively preparing a metal salt solution, an alkali solution and a complexing agent solution, adding the metal salt solution, the alkali solution and the complexing agent solution into a main reactor, and carrying out co-precipitation reaction under a certain condition; (2) dehydrating, washing and drying a solid precipitation product of the main reactor to prepare the carbonate precursor; (3) collecting supernatant liquor of the main reactor and centrifugally dehydrated wastewater and separating through an RO membrane, circularly taking pure water as washing water, and adding concentrated water into a secondary reactor; (4) adding the alkali solution and mixing the concentrated water components for carrying out secondary co-precipitation reaction, and circulating the solid precipitation product to the main reactor; and (5) efficiently evaporating and crystallizing the supernatant liquor of the secondary reactor to prepare a sodium sulfate by-product. The whole production process is clean; the metal salts arecompletely precipitated; the yield of the product is high; other chemicals do not need to be added; meanwhile, the method is free of emission of wastewater and free of heavy metal pollution problem.

The invention relates to a method for improving photoelectrode photoproduction carrier separation through compensation doping. The method includes the following steps that (1) a plurality of Mo:BiVO4 thin films are prepared on the surface of a conducting substrate, wherein Mo:BiVO4 is BiVO4 doped with Mo6+; and (2) a Co:BiVO4 thin film is prepared on the surface of each Mo:BiVO4 thin film, wherein Co:BiVO4 is BiVO4 doped with Co2+, and a preparing method of the Co:BiVO4 includes the following steps that a glacial acetic acid mixed solution of bismuth nitrate and cobalt nitrate and a diacetone solution of acetylketone vanadium are mixed to obtain a first total mixed solution, then the first total mixed solution is coated to the surface of the Mo:BiVO4 thin films, and drying and calcining are carried out to prepare a Mo:BiVO4 / Co:BiVO4 photoelectrode. Perfect lattice matching of the Mo:BiVO4 and the Co:BiVO4 greatly reduces the interface defect number, and compounding of carriers is further reduced.