High stability of electrocatalytic hydrogen evolution from Ru-WC/NC 0D-2D nanocomposites

Abstract

Pt based noble metal catalysts are important and efficient electrocatalysts during hydrogen evolution reaction (HER). However, the HER of Pt based noble metal catalysts have poor stability and high cost. Herein, Unique Ru loaded the tungsten carbide/nitrogen doped carbon (Ru-WC/NC) 0D-2D nanocomposites were fabricated by gas-phase reduction pyrolysis process to solve the problem of poor stability and high cost. Specifically, 0D WC-supported ultra-small Ru (∼2 nm) was anchored on nitrogen doped carbon nanosheets. Even with a remarkably low Ru loading of just 2.82 %, the developed catalyst achieves comparable high catalytic performance to that of a 20 % Pt/C catalyst and demonstrates superior stability. Under a current density of 10 mA cm⁻², the Ru₍₂₎-WC/NC catalyst shows an overpotential of 30 mV in acidic conditions and 51 mV in alkaline environments. Additionally, the overpotential of Ru₍₂₎-WC/NC lower than that of commercially 20 % Pt/C at high current densities exceeding 50 mA cm⁻². The total potential of water splitting for the two-electrode system comprising Ru₍₂₎-WC/NC with commercial ruthenium oxide was 1.56 V at 10mA cm⁻². Most importantly, the stability of Ru₍₂₎-WC/NC is much better than that of Pt/C. Theoretical calculation results further revealed that the ΔG_H* of Ru₍₂₎-WC/NC catalyst could be reduced through synergistic interactions between Ru and WC, thereby optimizing the kinetics of HER. This study offers both theoretical insights and practical methodologies for the synthesis and evaluation of electrocatalysts modified with low loading of noble metals.