Ru anchored on Co(OH)2 nanowire arrays as highly effective electrocatalyst for full water splitting

With the development of hydrogen energy, it is necessary to develop a cost-effective catalyst for electrochemical water splitting including hydrogen evolution reaction (HER) as well as oxygen evolution reaction (OER). Co-based composites are regarded as good catalysts toward OER, but weak H adsorption abilities lead to bad HER activities. Herein, Ru anchored on Co(OH)2 nanowire arrays (Ru/Co(OH)2 NWAs) as bifunctional catalysts for alkaline water splitting, are fabricated by hydrothermal process and subsequent immersion method. Ru/Co(OH)2 NWAs catalyst exhibits excellent activity for HER and OER, owing to strong electronic interaction of Ru participant and Co(OH)2 NWAs. To catalyze 10 mA cm−2 current density for HER and OER, Ru/Co(OH)2 NWAs catalyst only needs the overpotentials of 96 and 186 mV, respectively. An alkali electrolyzer assembled by bifunctional Ru/Co(OH)2 NWAs catalyst delivers 100 mA cm−2 at a cell voltage of 1.76 V, even superior than the couples of Pt/C and RuO2 electrodes (1.88 V).