Solid redox equilibrium via d-band centers regulation in the MoS2/Ni3S2 heterojunction for efficient selective oxidation of 5-hydroxymethylfurfural

The 5-Hydroxymethylfurfural electrocatalytic oxidation reaction (HMFOR) electrocatalytic oxidation reaction, in coupling with the hydrogen evolution reaction (HER), can replace the kinetically slow anodic oxygen evolution reaction (OER) to produce high value oxides and hydrogen. However, the commonly employed Ni-based electrocatalyst exhibits an unsatisfied performance due to the existence of OER. Here, we design and synthesize Ni3S2/MoS2/NiMoO4 catalyst for efficient and stable HMFOR reaction. Traced by in situ Raman technique, we demonstrate that the NiIII-OOH formed during the surface reconstruction process is the real reactive species for HMFOR. Moreover, the density functional theory results show the upward shift of d-band center in the reconstructed NiOOH/MoS2 is beneficial for the HMF adsorption, guarantee the smooth progression of redox equilibrium reactions. As a result, the prepared electrocatalyst shows a good HMFOR electrocatalytic performance in terms of selectivity (99.2%), conversion (96.7%) and Faraday efficiency (96.5%).