Cobalt-Tannin-Framework-Derived Amorphous Co-P/Co-N-C on N, P Co-Doped Porous Carbon with Abundant Active Moieties for Efficient Oxygen Reactions and Water Splitting

It remains a tremendous challenge to develop a low-cost, earth-abundant, and efficient catalyst with multifunctional activities for the hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and oxygen reduction reaction (ORR). Herein, a facile and scalable avenue was developed to prepare amorphous Co-P/Co-N-C supported on N, P co-doped porous carbon (Co-P/Co-N-C/NPC) with a large specific surface area (1462.9 m(2) g(-1)) and abundant reactive sites including Co-P, Co-N and NPC. The prepared electrocatalyst exhibits outstanding catalytic performance for HER (eta=234 mV at 10 mA cm(-2)), OER (eta=374 mV at 10 mA cm(-2)), and ORR (E-1/2=0.89 V, vs. reversible hydrogen electrode). Benefiting from the excellent HER performance and outstanding OER activity, the Co-P/Co-N-C/NPC delivers a current density of 10 mA cm(-2) for overall water splitting at a cell voltage of 1.59 V, which is comparable with the IrO2-Pt/C couple electrode.