Interconnected Network of Core-Shell CoP@CoBiPi for Efficient Water Oxidation Electrocatalysis under Near Neutral Conditions

Developing earth-abundant electrocatalysts for efficient and stable water oxidation under near neutral conditions is of great importance but still remains a key challenge. Herein, we demonstrate the development of an interconnected network of core-shell CoP@CoBiPi through anodic polarization of a CoP nanoarray in potassium borate aqueous electrolyte (KBi). This 3D CoP@CoBiPi exhibits high catalytic activity for water oxidation at pH9.2 and needs an overpotential () of only 410mV to drive a geometrical catalytic current density of 10mAcm(-2), with a high turnover frequency of 819h(-1) at an overpotential of 610mV. Remarkably, this catalyst also demonstrates high long-term electrochemical stability with its activity being maintained for at least 27h in KBi. This study provides us an attractive earth-abundant 3D catalyst electrode for water-splitting devices toward efficient and stable water oxidation under benign conditions.