A promising amendment for water splitters: Boosted oxygen evolution at a platinum, titanium oxide and manganese oxide hybrid catalyst

A hybrid catalyst composed of a platinum thin layer and modified with manganese oxide (MnOx) is recommended for the oxygen evolution reaction (OER). The Pt layer of the catalyst was physically sputtered onto a TiOx-coated Si substrate (this TiOx layer was sputtered inbetween the Si substrate and Pt layer to improve their adhesion and prevent their mutual diffusion). On top of the Pt layer, another thin TiOx layer (similar to 60 nm) was spun before the electrochemical deposition of MnOx. The investigation focused primarily to evaluate the impact of the catalysts annealing in oxygen atmosphere on its catalytic activity toward OER. Interestingly, before the modification with MnOx, a large catalytic enhancement both in activity (similar to 228 mV negative shift at 20 mA cm(-2) if compared to conventional bare Pt catalysts) and stability was achieved at the catalyst annealed at 600 degrees C toward OER in 0.5 M KOH. Surprisingly, the addition of MnOx to the catalyst synergized a boosted activity amplifying the negative shift to 470 mV at the same current density. Bunch of materials and electrochemical techniques were combined to reveal important remarks about the catalysts morphology, structure, composition and intrinsic activity which was attributed to electronic rather than geometric factors. (C) 2019 Production and hosting by Elsevier B.V.