Sacrificial templating synthesis of metal-organic framework hybrid nanosheets as efficient pre-electrocatalyst for oxygen evolution reaction in alkaline

Abstract

In this paper we report hybrid Ni/Fe metal-organic framework nanosheets tethered on nickel foam (Fe-Ni3S2-MOF/NF) synthesized via a two-step self-sacrificial templating strategy for efficient oxygen evolution reaction (OER) electrocatalysis. As-synthesized Fe-Ni3S2-MOF/NF exhibits superb OER catalytic performance in alkaline solution. It requires only 250 mV overpotential to achieve 100 mA cm−2 current density with excellent stability of over 48 h and considerably surpasses its analogs and the benchmark RuO2 catalyst. The residual metal sulphide clusters incorporated in the hybrid nanosheets are found to be critical for the excellent OER performance of Fe-Ni3S2-MOF/NF. They confer large specific surface areas and facilitate the electron transportation for efficient OER electrocatalysis. Moreover, they modulate the electronic state of surface metal sites on nanosheets to enhance the intrinsic OER activity.