Effective electrocatalytic xylose oxidation coupling hydrogen production on hierarchical microcolumn NiMoO4 array

The simultaneous realization of biomass conversion and clean energy hydrogen (H 2 ) production remains a desirable but challenging objective. Herein, we present a strategy that simultaneously enables anodic electrocatalytic xylose oxidation (EXO) coupling with the cathodic hydrogen evolution reaction (HER). In the EXO process, the hierarchical microcolumn NiMoO 4 array exhibits excellent performance, achieving 200 and 231 mV reduction of overpotential compared to the oxygen evolution reaction at 10 and 50 mA cm −2 , respectively, and an overpotential of 130 mV lower than that of Ni foam at 50 mA cm −2 . The mechanism studies reveal that the OH* are effective active species to facilitate the EXO process. For HER, the P-doped NiMoO 4 (P-NiMoO 4 ) electrode exhibits remarkable HER performance, achieving 64 and 197 mV overpotential at 10 and 50 mA∙cm −2 , respectively. These are far superior to most of the previous studies. The P-NiMoO 4 electrode maintains high durability over 110 h across various current densities. The incorporation of P modifies the electronic environment of NiMoO 4 , enhancing the adsorption of H*, and thereby improving HER activity. In the assembled system, the paired reactions have low voltages of 0.81 and 1.53 V at 10 and 50 mA cm −2 , respectively, a high Faradaic efficiency of 80%, and decent durability over 100 h. This work offers a guideline for the sustainable synthesis of value-added chemicals and clean H 2 via paired electrocatalytic biomass refining. ● Anodic xylose oxidation coupling with cathodic H 2 evolution system is constructed. ● EPR reveals OH* as an effective active species to facilitate xylose electrooxidation. ● The high-value formic acid and green H 2 are generated synchronously and stably over 100 h. ● The doping of P modifies the electronic environment of NiMoO 4 to improve HER activity. ● Hierarchical microcolumn NiMoO 4 with porous structure enhances mass diffusion kinetics.