9results about How to "Optimize electronic structure" patented technology

The application provides a self-supporting Ni-Fe-Mn oxygen evolution electrocatalyst and a preparation method thereof, and belongs to the technical field of catalytic material preparation. The Ni, Fe and Mn metal raw materials are repeatedly smelted, and after smelting, suction casting is carried out to obtain a cast plate. The cast plate is subjected to homogenization treatment, and then is cut and polished. Finally, etching is carried out in a nitric acid solution to obtain the self-supporting Ni-Fe-Mn oxygen evolution electrocatalyst. The self-supporting electrocatalyst is prepared by the method of arc smelting, heat treatment and chemical etching, and has the advantages of simple preparation process, easy industrialization, adjustable size, excellent stability and excellent OER performance.

A heterovalent copper-doped lithium cobalt phosphate cathode material and its preparation method are disclosed, belonging to the technical field of lithium-ion battery cathode materials. The general chemical formula of the heterovalent copper-doped lithium cobalt phosphate cathode material is LiCu. x Co 1‑x PO4, where 0 < x ≤ 0.1; it has an orthorhombic Pnma olivine structure, Co 2+ The cobalt phosphate material occupies the 4c ​​site of the CoO6 octahedron; copper is doped into the lattice as monovalent copper, and heterovalent cobalt sites are substituted. The method is as follows: First, lithium, copper, cobalt, and phosphorus sources are mixed uniformly to obtain a precursor mixture; second, the precursor mixture undergoes a high-temperature solid-state reaction under a protective atmosphere, followed by calcination at 600-800℃ for 4-8 hours; finally, it is cooled to room temperature to obtain the cathode material. This invention successfully activates the electrochemical activity of lithium cobalt phosphate, significantly improving the initial charge-discharge capacity compared to the pure phase; the heterovalent substitution-induced cobalt valence state change helps optimize the electronic structure of the material and improve conductivity; the preparation process helps reduce side reactions and impurity phase formation, is simple, has good reproducibility, and is easy to scale up industrially.

The invention relates to a preparation method of a high-stability chalcogenide modified Fe-N-C catalyst based on a confinement gas phase migration strategy, which comprises the following steps: S1, etching the Fe-N-C catalyst by using an etching gas decomposed from ammonium chloride at high temperature to obtain a defect-rich Fe-N-C catalyst; s2, the chalcogenide powder and the Fe-N-C catalyst rich in defects are mixed to be uniform, the mixture is placed in a vacuum and closed container, pyrolysis treatment is conducted at the temperature not lower than the temperature at which the chalcogenide powder is converted into chalcogenide steam, the chalcogenide modified Fe-N-C catalyst is obtained, and the chalcogenide powder is sulfur powder or selenium powder or tellurium powder. According to the method, a confinement gas phase migration strategy is adopted, a closed confinement reaction space is constructed, accurate preparation of the sulfur group modified Fe-N-C catalyst is achieved, and the problems that the stability of the Fe-N-C catalyst is insufficient and a volatile element doping process is difficult to control can be effectively solved.

This invention discloses a method for preparing a BiOI-based catalyst, the BiOI-based catalyst itself, and its applications, belonging to the field of carbon dioxide conversion and utilization. It overcomes the problems of insufficient stability and low product yield when BiOI is used as an ECR catalyst in existing technologies. The preparation method of the BiOI-based catalyst of this invention includes the following steps: Step 1, obtaining BiOI; Step 2, mixing the BiOI, a sulfur source, and a first solvent, heating and reacting to obtain S-BiOI powder; the mass ratio of BiOI to the sulfur source is 35.2:(0.25-4). The BiOI-based catalyst of this invention exhibits improved product yield and good stability during the reduction of carbon dioxide to formate or formic acid, maintaining high activity during long-term ECR formic acid production.

The invention discloses a nickel ferrite catalytic material as well as a preparation method and application of the nickel ferrite catalytic material with a controllable crystal face, and belongs to the technical field of electro-catalysis. The preparation method comprises the following steps: fixing a conductive substrate in a cavity of a magnetron sputtering coating machine, ensuring that the substrate is parallel to a target surface, and setting a target-substrate distance to be 2-20cm; the cavity of the magnetron sputtering coating machine is pre-vacuumized, and glow cleaning is carried out after inert gas is introduced; nickel ferrite is used as a target material, a nickel ferrite catalytic layer is deposited in situ on the surface of the conductive base material through physical vapor deposition, and the nickel ferrite catalytic material is obtained. According to the method, the magnetron sputtering technology is adopted, the target-substrate distance is changed, effective regulation and control over the nickel ferrite crystal face structure are successfully achieved, and the electronic structure and the surface adsorption / desorption energy barrier of the material can be remarkably influenced by the fine change of the crystal structure; therefore, three bottlenecks of low activity, poor stability and slow dynamics confronted by nickel ferrite as an OER catalyst are synchronously broken through, and key material and technical support is provided for commercial application of an AEM electrolytic cell.

The invention belongs to the technical field of catalysts, and particularly discloses a Pd monatomic and nanoparticle synergistic catalyst and a preparation method and application thereof.The active component Pd of the catalyst is loaded on a zirconium phosphate carrier in the forms of monatomic and nanoparticles; the zirconium phosphate carrier is of an amorphous structure, and the specific surface area is 120-180m < 2 > / g; and the mass fraction of the active component Pd in the catalyst is 0.3-3 wt%. The invention solves the problem that the activity, stability and selectivity of the catalyst in the alkyne semi-hydrogenation reaction cannot be combined at the same time through the simple synthesis method.

The invention relates to the technical field of electro-catalysis, and discloses a water electrolysis hydrogen evolution method which comprises the following steps: under a water electrolysis condition, taking a water electrolysis hydrogen evolution catalytic electrode as a working electrode to carry out water electrolysis reaction; wherein the water electrolysis hydrogen evolution catalytic electrode comprises a conductive substrate and a catalytic material compounded on the surface of the conductive substrate, and the catalytic material comprises a carbon-coated platinum-based alloy nano material and conductive carbon black; wherein the carbon-coated platinum-based alloy nano material contains a platinum-metal M alloy particle inner core and a graphitized carbon layer coated on the surface of the platinum-metal M alloy particle inner core, and the metal M is selected from at least one of Ni, Co and Zn. The water electrolysis hydrogen evolution method provided by the invention has relatively low reaction overpotential and relatively high reaction activity and stability.

The invention discloses a preparation method of a dual-mechanism oxygen evolution reaction spinel oxide electrocatalyst based on a strategy of partially filling oxygen vacancies with anions, and relates to a preparation method of an oxygen evolution reaction spinel oxide electrocatalyst. The technical problems that an existing pure spinel oxide is low in catalytic efficiency and unstable in structure are solved. The preparation method comprises the following steps: 1, preparing a self-supporting spinel oxide electrode material; 2, preparing a self-supporting oxygen vacancy enriched spinel oxide electrode material; 3, preparing a self-supporting oxygen vacancy part anion filling type catalyst; according to the invention, an oxygen vacancy-anion partial filling strategy is utilized to regulate and control the local structure and the electronic state of the spinel oxide. The overpotential of the prepared Co3O4-VO-S / NF catalyst in 1.0 M KOH at the current density of 50 mA cm <-2 > is as low as 301 mV, and the Co3O4-VO-S / NF catalyst can stably run for more than 120 hours and can be used in the field of hydrogen production by water electrolysis.

The invention provides a selenium monatomic coupling PtNiMoPdRh alloy catalyst as well as a preparation method and application thereof, and belongs to the technical field of metal nano catalysts. The preparation method comprises the following steps: performing constant-temperature heat treatment on carbon-selenium mixed powder at 680-700 DEG C to obtain a carbon-selenium compound, uniformly mixing a metal source, a surfactant, a reducing agent and the carbon-selenium compound in a solvent, and reacting at 200-240 DEG C to obtain the selenium monatomic coupled PtNiMoPdRh alloy catalyst. The selenium monatomic coupled PtNiMoPdRh alloy catalyst has the advantages of high conductivity, strong metal-carrier interaction, sufficient active sites, high structural stability, high catalytic activity and the like, and can be used for catalyzing water electrolysis for hydrogen production; in addition, the method is simple, easy to operate, short in reaction time and low in cost, and has good popularization and application prospects.