Suppressing catalyst reconstruction in neutral electrolyte: stabilizing Co-O-Mo point-to-point connection of cobalt molybdate by tungsten doping for oxygen evolution reaction

Neutral oxygen evolution reaction (OER) is a crucial half-reaction for electrocatalytic chemical production under mild condition, but with limited development due to low activity and poor stability. Herein, a tungsten-doped cobalt molybdate (WDCMO) catalyst was synthesized for efficient and durable OER under neutral electrolyte. It is demonstrated that catalyst reconstruction is suppressed by W doping, which stabilizes the Co-O-Mo point-to-point connection in CoMoO 4 architecture and stimulates to a lower valence state of active sites over the surface phase. Thereby, the surface structure maintains to avoid compound dissolution caused by over-oxidation during OER. Meanwhile, the WDCMO catalyst promotes charge transfer and optimizes *OH intermediate adsorption, which improves reaction kinetics and intrinsic activity. Consequently, the WDCMO electrode exhibits an overpotential of 302 mV at 10 mA cm –2 in neutral electrolyte with an improvement of 182 mV compared with CoMoO 4 electrode. Furthermore, W doping significantly improves the electrode stability from 50 h to more than 320 h, with a suppressive potential attenuation from 2.82 to 0.29 mV h –1 . This work will shed new light on designing rational electrocatalysts for neutral OER.