Full Water Splitting Electrocatalyzed by NiWO4 Nanowire Array

It is attractive to develop an effective bifunctional electrocatalyst for full water splitting. In this Letter, we report that a NiWO4 nanowire array on a Ti mesh (NiWO4/TM) is a high-performance and stable water-splitting electrocatalyst at alkaline pH. As a 3D electrocatalyst, such a NiWO4/TM attains 20 mA cm–2 under overpotentials of 101 mV for cathodic water reduction and 322 mV for anodic water oxidation. We also demonstrate the use of NiWO4/TM to make a two-electrode electrolyzer capable of driving 20 mA cm–2 at a cell voltage of 1.65 V.