Heterostructured Inter-Doped Ruthenium-Cobalt Oxide Hollow Nanosheet Arrays for Highly Efficient Overall Water Splitting.

The development of transition metal oxides (TMOs)-based bifunctional catalysts toward efficient overall water splitting through delicate control of composition and structure is a challenging task. Herein, we report rational design and controllable fabrication of unique heterostructured inter-doped ruthenium-cobalt oxide ((Ru-Co)O x ) hollow nanosheet arrays on carbon cloth. Benefiting from the desirable compositional and structural advantages of more exposed active sites, optimized electronic structure, and interfacial synergy effect, the (Ru-Co)O x nanoarrays exhibited outstanding performance as a bifunctional catalyst. Particularly, they showed a remarkable hydrogen evolution reaction (HER) activity with an overpotential of 44.1 mV at 10 mA cm -2 and a small Tafel slope of 23.5 mV dec -1 , as well as an excellent oxygen evolution reaction (OER) activity with an overpotential of 171.2 mV at 10 mA cm -2 . As a result, a very low cell voltage of 1.488 V was needed at 10 mA cm -2 for alkaline overall water splitting.