Nickel-cobalt phosphide terephthalic acid nano-heterojunction as excellent bifunctional electrocatalyst for overall water splitting

Abstract

Recent research has focused on preparing excellent and inexpensive bifunctional transition metal electrocatalysts, which is challenging. Herein, a facile synthesis strategy for preparing self-supported nickel-cobalt phosphides using terephthalic acid (H2BDC) as metal-organic framework (MOF) precursor is reported. The incorporation of the MOF precursors modulated the electronic structures and improved the performance of the bimetallic transition metal phosphides with the as-prepared electrocatalyst requiring low overpotentials of 170 mV and 323 mV to reach 50 mAcm−2 for HER and OER, respectively. Moreover, the electrocatalyst is employed in an alkaline water electrolyzer and requires 1.57 V to attain a current density of 10 mAcm−2 with long-term stability, surpassing many reported MOF-derived bimetallic transition metal phosphide (TMPs) electrocatalysts. This work explores the incorporation of a rarely studied MOF precursor into self-supported bimetallic TMPs and opens the prospects of designing efficient MOF-derived electrocatalysts for overall water splitting.