Hydrogen spillover effect – harnessing hydrogen evolution reaction from diverse carbon-based supports with a tungsten oxide catalyst

Abstract

Engineering competent electrocatalysts to accelerate the production of sustainable hydrogen fuel is an important criterion in electrochemical water splitting. The hydrogen evolution reaction (HER) as an equally crucial step in water electrolysis has been in the spotlight for more than a decade. Nevertheless, understanding the mechanistic insights between the multifunctional catalytic sites, especially in sophisticated nanohybrids are not much delved into here, an inexpensive fabrication of a ‘3D electrocatalyst’ with the well-established WO₃ metal oxide is layered with different carbon entities, both two dimensional and bulk, to decode the mechanism of hydrogen spillover effect (HSPE) and understand their stability profile through Pourbaix profiles for heterogeneous catalysis of HER in both acidic and alkaline environments. The HER kinetics of the reduced graphene sheets with WO₃ could stand on par with the existing state-of-the-art noble electrocatalyst – Pt. Sequentially strong electrocatalytic kinetics with high durability and intrinsic activity conclusively make the freestanding 3D architecture an attractive candidate to scale up as an efficient electrocatalyst for the HER. The present work emphasizes the need to understand the mechanism for designing and developing HER electrocatalysts based on the conductive nature and electron transport pathways on different carbon supports.