▎ 摘　　要

NOVELTY - Carbon-supported iridium(IV) oxide-iridium heterojunction composite catalyst with strawberry-shaped structure, is claimed. The composite catalyst is black solid powder. The iridium(IV) oxide-iridium heterojunction is uniformly supported on the surface of the carbon support. The amorphous iridium(IV) oxide layer is epitaxially on the surface of the metal iridium. The thickness of the iridium(IV) oxide layer is less than 1 nanometer, and the ultra-thin iridium(IV) oxide layer is in a state of low chemical coordination and stress shrinkage. USE - The composite catalyst is useful for hydrogen evolution and oxygen evolution in electrolysis of water, preferably devices involving oxygen evolution reaction or hydrogen evolution reaction, e.g. electrolyzed water tank and integrated renewable fuel cell (claimed), electrode electrocatalyst for oxygen evolution and hydrogen evolution reaction in electrolysis tanks, rechargeable zinc-air batteries and other devices. ADVANTAGE - The catalyst has excellent electrocatalytic activity for water splitting. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparing the composite catalyst, comprising (1) using metal iridium salt as precursor, carbon material as carrier, and organic amine as stabilizer, dispersant and anchor of metal salt, and fully mixing iridium salt and carbon carrier through solution dispersion, and (2) reducing the metal iridium by carbothermal then under inert atmosphere and uniformly loading on the carbon support, where the stabilizer and dispersant inhibit the growth of the catalyst nanocrystals and regulates the composition and structure of the iridium-based catalyst, and preparing carbon-supported iridium(IV) oxide-iridium heterojunction composite catalyst with strawberry-shaped structure.