New approach to produce cubic-WC at low temperature for hydrogen evolution reaction

López E.O.; Arias-Pinedo O.M.; Soria-Martínez R.; Bazan-Aguilar A.; García G.; Bernardo P.L.; Checca N.R.; Mello A.; Baena-Moncada A.M. · International Journal of Hydrogen Energy (2024) · DOI: 10.1016/j.ijhydene.2024.03.107

Resumen

A novel catalyst, a nanostructured cubic-WC (c-WC) flat film, is introduced for the hydrogen evolution reaction (HER) using a specialized magnetron sputtering system. This method results in over 94% crystalline c-WC0.95 formation at room temperature, featuring high-density stacking faults and twin defects. The catalytic performance of the c-WC film for HER is investigated through theoretical simulations and experimental studies. Density-functional theory (DFT) suggests that the c-WC (100) surface exhibits faster reaction kinetics than c-WC (111) surface, approaching the efficiency of Pt (111) surfaces. Experimentally, the c-WC0.95 film exhibits a high electrochemical surface area and increased active sites due to surface defects. Differential electrochemical mass spectrometry (DEMS) confirms an onset potential for HER of −50.0 mV for c-WC0.95 films and establishes electrodesorption as the rate-determining step. Overall, the c-WC film emerges as a cost-effective and efficient catalyst for green hydrogen production, showcasing excellent reproducibility and electrochemical stability.

Instituciones: Universidad Nacional de Ingeniería; Universidad Tecnológica del Perú