The invention discloses a preparation method of N-doped
porous carbon coated nano-particles (Co@Ir / NC-x, and x is the quality ratio of Ir) of a Co-Ir core-shell structure and application of the N-doped
porous carbon coated nano-particles of the Co-Ir core-shell structure to catalytic
water splitting. The preparation method has the advantages that (1) the preparation process is simple and direct, and
energy consumption is low, specifically, Co / NC obtained after a
zeolite imidazole framework material (ZIF-67 for short) is calcined is directly subjected to Galvanic replacement with Ir<3+> at theroom temperature, high temperature and
high pressure are not needed, and accordingly the
energy consumption is low; (2) the catalytic performance is good, and the stability is high, specifically, a Co@Ir / NC-10% sample is in a 1M KOH solution, in an
oxygen producing test, the
current density is 10 mA cm<-2>, the
overpotential is 280 mV, and the performance is higher than IrO2; in a
hydrogen producing test, the
current density is 10 mA cm<-2>, the
overpotential is -121 mV; besides, after a
stability test of 12 h, the
oxygen producing activity of IrO2 is attenuated by 55.8% while the
oxygen producing activity of Co@Ir / NC-10% is attenuated only by 20.6%, and the
hydrogen producing stability of Co@Ir / NC-10% is far higher than that of commercial Pt / C under the same conditions; and (3) the catalyst cost is low and the Co source is wide, specifically, the nano-particles are of the core-shell structure with Co as a core and Ir as a shell, the amount of Ir is reduced on the basis of more exposedcatalytic activity sites, a core
metal precursor Co is wide in source and low in cost, the catalyst cost is greatly reduced, and great commercial application prospects are achieved.