Carbon-covered Tungsten Carbide Nanoparticles： Solid-state Synthesis and Application as Stable Electrocatalysts for the Hydrogen Evolution Reaction

Carbon-covered tungsten carbide nanoparticles（cc-WCNPs） were prepared via a one-step solid-statereaction between W（CO）6 and triphenylamine at 850 ℃ tinder a sealed Ar atmosphere. As novel electrocatalysts forthe hydrogen evolution reaction（HER）, cc-WCNPs exhibit an onset potential of-0.14 V vs. reversible hydrogenelectrode（RHE） and a Tafel slope of 64.6 mV/dec in a 0.5mol/L H2SO4 solution. Additionally, these cc-WCNPscatalysts also show excellent electrocatalytic stability after 1000 cycles.