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

Graphical From tannic acid to water splitting : 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 and abundant reactive sites is prepared. The material exhibits outstanding catalytic performance for the hydrogen evolution reaction (HER, η =234 mV at 10 mA cm −2 ), oxygen evolution reaction (OER, η =374 mV at 10 mA cm −2 ), and oxygen reduction reaction (ORR, E 1/2 =0.89 V, vs. RHE). 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 ( η =234 mV at 10 mA cm −2 ), OER ( η =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 IrO 2 –Pt/C couple electrode.