4results about How to "Increased electrochemically active surface area" patented technology

This invention relates to a method for preparing a hollow spherical, chlorine-free PtCu / C catalyst and its application. The preparation method includes the following steps: calcining a carbon support in a reducing atmosphere; dispersing the calcined carbon support in an alcohol-water mixture and adding an oxidant for a hydrothermal reaction; uniformly dispersing the hydrothermally reacted carbon support in the alcohol-water mixture and adjusting the pH to acidic to obtain a carbon support suspension; and adding Pt(NH4+)4 to the carbon support. 3 ) 4 (OH) 2 Solution and Cu(NH4) 3 ) 4 (OH) 2 A carbon-supported suspension was added to the solution, followed by reduction with a reducing agent to obtain a chlorine-free PtCu / C catalyst, wherein the PtCu is a nano-hollow sphere structure. This invention eliminates the contamination caused by residual Cl ions in existing catalysts; the synergistic and ligand effects between Pt and Cu atoms weaken the adsorption strength of oxygen-containing intermediates at Pt sites during the ORR process, lowering the reaction energy barrier of the catalyst in the oxygen reduction process; the high atomic utilization and large electrochemical active surface area of ​​the hollow sphere structure also facilitate the catalytic reaction, resulting in excellent ORR electrocatalytic activity and stability of the catalyst.

This invention discloses a carbon nanotube-based catalyst in which metal single atoms and nanocrystals coexist, its preparation method, and its application, relating to the field of catalyst technology. This invention utilizes highly conductive and stable carbon oxide nanotubes as a dedicated support, employing an in-situ construction strategy to simultaneously stabilize single atoms of manganese and molybdenum and their nanoclusters under high-temperature conditions. By leveraging the interfacial electronic coupling and orbital hybridization effect between the two, synergistic regulation of the adsorption energy of oxygen intermediates is achieved. This fundamentally overcomes the limitation of high energy barriers in multi-electron coupling reactions at pure single-atom sites. While significantly improving the bifunctional catalytic activity of oxygen reduction and oxygen evolution reactions, it effectively inhibits the migration and aggregation of metal species during preparation and operation, solving the core problem of balancing activity and stability in single-atom catalysts.

The invention provides an electrolytic water oxygen evolution catalyst with a NiFe2O4-coated CoCr-LDH heterostructure, which is prepared by the following steps: adding nickel salt, ferric salt, ammonium fluoride and urea into water, and uniformly stirring to obtain a mixed solution; immersing a clean foam substrate in the mixed solution, placing in a reaction kettle, and carrying out hydrothermal compounding at a certain hydrothermal temperature for a certain hydrothermal time, so as to grow a NiFe-LDH sheet on the surface of the foam nickel; cleaning and drying the obtained sample, and then carrying out heat treatment at a proper temperature to obtain a supported NiFe2O4 material; the preparation method comprises the following steps: taking a NiFe2O4 material as a working electrode, dipping the NiFe2O4 material in a reaction solution containing cobalt salt and chromium salt, carrying out electro-deposition reaction, and depositing a thin layer of CoCr-LDH nanosheets on the surface of the material; the obtained working electrode is washed and dried, and the water electrolysis oxygen evolution catalyst with the NiFe2O4 and CoCr-LDH heterostructure is obtained. The catalyst shows excellent oxygen evolution reaction activity and excellent catalytic stability under an alkaline condition; the method is low in raw material cost, simple in process, low in equipment requirement and high in repeatability.

The application discloses a copper-based compound for electrocatalytic sulfur ion oxidation assisted hydrogen production and a preparation method and application thereof, and belongs to the field of electrochemical catalysis. The method comprises the following steps: S1, dissolving copper nitrate in a solvent under ultrasonic stirring to configure a copper salt solution, immersing pretreated foamed nickel in the copper salt solution to obtain a mixture; S2, sealing the mixture in a stainless steel autoclave with a polytetrafluoroethylene liner, and performing a reaction under heating; S3, after the reaction, cooling to room temperature, cleaning the foamed nickel after the reaction with deionized water, and drying to obtain a product Cu2(OH)3NO3@NF, which solves the problems of existing catalyst deactivation and surface passivation caused by accumulation of elemental sulfur or polysulfides on active sites.