A WOx mediated interface boosts the activity and stability of Pt-catalyst for alkaline water splitting

Water splitting offers a clean way to produce hydrogen, in which, an efficient catalyst interface is one of the key factors to boot the activity and stability. Here, using polyoxotungstate (POT) as precursor, Pt-based bifunctional catalysts were fabricated, which are composed of Pt, WO x and graphene (Pt-WO 3−x @rGO). The Pt-WO 3−x @rGO (1.58% Pt-loading) catalyst shows an enhanced catalytic activity, namely, overpotentials of 37 mV for Hydrogen evolution reaction (HER) and 174 mV for Oxygen evolution reaction (OER), and achieves a working voltage of 1.55 V at 10 mA cm −2 for water splitting in alkaline-medium. Electrochemical analyses and DFT calculation suggest that the WO x mediated interface (Pt 0 ⋅⋅⋅O − W) plays a key role to enhance the electron transfer and reduce the activation energy for both HER and OER. Moreover, this kind of Pt 0 ⋅⋅⋅O − W interface enhances the Pt based catalyst stability in alkaline-medium significantly.