Synergistic interface engineering and structural optimization of Fe-BDC/CoWO4/NF electrodes for super-efficient seawater oxidation

Designing and developing high-efficient and durable non-precious-metal oxygen evolution reaction (OER) electrocatalysts is relevant for hydrogen generation from seawater splitting. Herein, a novel interfacial-coupled Fe-BDC/CoWO4/NF nanosheet array has been demonstrated via a two-step solvothermal method, which can effectively accelerate OER with an ultra-low overpotential of 254 mV at 100 mA cm−2 in 1.0 M KOH. More interestingly, it exhibits overpotentials of 290, 296, and 301 mV at 100 mA cm−2, when using 1.0 M KOH with 0.5, 1.0, and 2.0 M NaCl as simulated seawater and a lifetime of more than 250 h. The excellent performance for OER is benefit from the distinctive interfacial-structure, optimizing the OER process energy barrier of and lowering the adsorption energy of oxygen-containing intermediates, effectively speeding up the OER kinetics. This work opens a new strategy for designing versatile base metal OER electrocatalysts.