Universal synthesis of coral-like ternary MOF-derived sulfides as efficient OER electrocatalysts

The strategy of synthesizing high-efficiency oxygen evolution reaction (OER) catalysts using sacrificing metal-organic framework (MOF) templates is considered promising. However, few reports have focused on improving the intrinsic electrocatalytic activity of the MOF templates. Herein, we have developed a universal synthesis method for synthesizing a series of ternary coral-like FeNiM (M = Zn, Co and Cd) MOF templates. Benefitting from the synergistic effect, these trimetallic templates exhibit identical morphologies and outstanding OER performance compared to mono-metal templates. Moreover, transition metal sulfides (FeNiZnS) have been synthesized to enhance the overall electrical conductivity of catalyst materials. Optimized FeNiZnS-1 exhibits a minimal overpotential of 249 mV to achieve a current density of 10 mA cm-2, alongside outstanding electrochemical durability over 60 h in chronopotentiometry (CP) testing. The two-electrode couple FeNiZnS-1//Pt/C achieves a cell voltage of 1.54 V at 10 mA cm-2 for overall water splitting in 1 M KOH solution. Synthesize and tune a series of trimetallic sulfides to achieve efficient catalysis for the OER.