A low Pt-loaded electrode electrochemically synthesized from bulk metal for electrocatalytic applications

Abstract

The design of economical, efficient, and durable low-Pt catalysts is one of the directions in developing energy storage and conversion technologies. Herein, a Pt/WC_1−x/WO₃ self-supported electrode with a low Pt-loading (17.4 μg cm⁻²) was synthesized from bulk metals by an anodization coupled electrodeposition method followed by a carburization reduction process. The electrode exhibits an overpotential of 89.6 mV at 200 mA cm⁻² for the hydrogen evolution reaction (HER) with excellent stability. Its highest mass activity for the methanol oxidation reaction (MOR) is 1.18 A mg⁻¹ Pt, which is 2.46 times higher than that of a 20% Pt/C catalyst. This self-supporting electrode also shows excellent stability and resistance to CO poisoning. These can be attributed to the synergistic effects among Pt, WC_1−x and WO₃, and the heterogeneous interface between them, which accelerates the process of hydrogen absorption and desorption on their surface. These results suggest that the anodization coupled electrodeposition method is an efficient approach to design low Pt-loaded self-supporting electrodes with high activity and stability.