▎ 摘　　要

NOVELTY - A self-supporting layered bimetallic phosphide-graphene composite catalyst comprises a carrier and an active component, where the active component is self-supporting layered composite material in which bimetallic phosphide nanoparticles are uniformly dispersed on graphene. The bimetallic phosphide has an atomic heterojunction structure. The carrier is selected from one or more of foamed nickel, foamed copper, carbon cloth, aluminum oxide and titanium oxide. The bimetal is selected from copper, nickel, iron, cobalt, manganese, zinc, and molybdenum. The molar ratio of metal (1) and metal (2) in bimetal is 10:1-1:10. USE - Self-supporting layered bimetallic phosphide-graphene composite catalyst for electrochemical hydrogen evolution reaction, oxygen evolution reaction and electrochemical total water splitting (claimed). ADVANTAGE - The nano-electrocatalyst has abundant interface defects and vacancies, enriches active sites, improves the electronic interaction and electrocatalytic performance, has excellent stability during entire water separation process, and is maintained for 24 hours without decay. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: 1. the preparation method of composite catalyst, which involves (1) cutting carrier into small blocks, ultrasonically washing, and drying with inert gas, (2) stirring bimetallic oxide precursor, structure-directing agent and precipitating agent to obtain mixed solution, soaking the carrier obtained in the step (1) into the mixed solution, placing in a stainless steel reactor, sealing, hydrothermally reacting, cooling, washing and drying, (3) mixing the product obtained in the step (2) with solvent, adding hexaethynylbenzene, reacting, washing and drying, and (4) heating the product obtained in the step (3) and phosphorus source under inert atmosphere, reacting, and cooling to obtain a final product; and 2.the use of composite catalyst for electrochemical hydrogen evolution reaction, oxygen evolution reaction and electrochemical total water splitting.