Molybdenum Carbide Nanoparticles on Carbon Nanotubes and Carbon Xerogel: Low‐Cost Cathodes for Hydrogen Production by Alkaline Water Electrolysis

Abstract

Abstract Low‐cost molybdenum carbide (Mo 2 C) nanoparticles supported on carbon nanotubes (CNTs) and on carbon xerogel (CXG) were prepared and their activity for the hydrogen evolution reaction (HER) was evaluated in 8 m KOH aqueous electrolyte at 25–85 °C. Measurements of the HER by linear scan voltammetry allowed us to determine Tafel slopes of 71 and 74 mV dec −1 at 25 °C for Mo 2 C/CNT and Mo 2 C/CXG, respectively. Stability tests were also performed, which showed the steady performance of the two electrocatalysts. Moreover, the HER kinetics at Mo 2 C/CNT was enhanced significantly after the long‐term stability tests. The specific activity of both materials was high, and a higher stability was obtained for the activated Mo 2 C/CNT (40 A g −1 at −0.40 V vs. the reversible hydrogen electrode).