MOF-derived V-CoxP@NC nanoarchitectures for highly enhanced electrocatalytic water splitting through electronical tuning

Achieving overall water splitting in the same electrolyte remains a challenge for a cost-effective and durable bifunctional catalyst. Doping foreign element into intrinsic materials is an effective way to enhance the electrocatalytic activity, thus we design a facile method to synthesize a novel vanadium doped mixture of CoP and Co2P nanoparticles encapsulated in zeolitic imidazolate framework-67 (ZIF-67) derived nitrogen doped carbon (V-CoxP@NC NPs) in this work for the first time. Benefiting from the protection of carbon shell and regulation of electronic structure through doping vanadium and phase-mixing CoP and Co2P, the V-CoxP@NC NPs show excellent electrocatalytic performance in both oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) in 1.0 M KOH. Using V-CoxP@NC NPs to construct overall water splitting (OWS) device, the electrolyzer achieves the current density of 10 mA cm(-2) with a small cell voltage of 1.54 V, exhibiting remarkable activity and continuous work for 20 h without obvious fluctuation. (C) 2020 Elsevier Ltd. All rights reserved.