Localized electronic reconfiguration at CoNi-BTC-MOFs to accelerate oxygen evolution reaction

Abstract

To efficiently control oxygen evolution reaction (OER) at electrocatalysts holds enormous promise for large-scale production of clean energy, but faces the scarcity of practical regulation strategies due to underexplored catalytic mechanism. Herein, a facile and feasible strategy is developed involving metal-metal super-exchange interaction to manipulate the electronic state configuration of catalysts, and the as-synthesized Ni-doped Co-1,3,5-benzenetricarboxylic acid Metal-Organic Frameworks (MOFs) only require an overpotential as low as 260 mV to reach a large current of 200 mA cm−2, which is much lower than 400 mV for the commercial RuO2 catalyst. The introduced Ni atoms lead to more broadly occupied states and d-band center close to the Fermi energy level for the spin-polarization of the electrons in Co atoms, thus decreasing the orbital occupancy to facilitate the adsorption/desorption of the reaction intermediates and lowering the rate-determining step barrier to accelerate OER. Our findings have an important paradigm role in the design of electrocatalysts with high performance for oxygen evolution reaction.