▎ 摘　　要

NOVELTY - Noble metal/carbon nano composite catalyst comprises a carbon matrix and noble metal nano particles combined on the carbon matrix. The grain diameter of the noble metal nanoparticle is 1-3 nanometer (nm). The carbon matrix is reducing graphene oxide and/or carbon nano tube. USE - Noble metal/carbon nano composite catalyst used for electrolytic water reaction such as electrolytic water hydrogen production reaction, where the electrolyte is acid washing, neutral or alkaline. The glassy carbon electrode modified by the noble metal/carbon nano-composite catalyst used as the working electrode. The calomel electrode or silver-silver chloride electrode is reference electrode. The graphite electrode is counter electrode (claimed). ADVANTAGE - Noble metal/carbon nano composite catalyst realizes efficient electrolytic water to prepare hydrogen, the current density reaches to -10 milliampere/cm2 under the alkaline condition and the over-potential is 18.7 millivolt. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a method for preparing noble metal/carbon nano composite catalyst by colloid method, which involves: (A) using alkali-ethylene glycol method to prepare noble metal nano colloid, marked as noble metal/glycol colloid; (B) dispersing the carbon material with oxygen-containing functional group on the surface into water to obtain the carbon material dispersion; (C) mixing and stirring the iridium nano colloid and the carbon material dispersion liquid; (D) heating to obtain the first mixture; and (E) separating, drying to obtain the noble metal/carbonnano composite catalyst.