The role of oxygen-vacancy in bifunctional indium oxyhydroxide catalysts for electrochemical coupling of biomass valorization with CO₂ conversion

Electrochemical coupling of biomass valorization with carbon dioxide (CO₂) conversion provides a promising approach to generate value-added chemicals. Oxygen-vacancy-rich indium oxyhydroxide (InOOH-O_v) is developed as a bifunctional catalyst for CO₂ reduction to formate and 5-hydroxymethylfurfural electrooxidation to 2,5-furandicarboxylic acid, with faradaic efficiencies over 90.0% at optimized potentials. Oxygen vacancies cause lattice distortion and charge redistribution, protecting InOOH-O_v from reduction during CO₂ conversion and increasing 5-hydroxymethylfurfural adsorption. A pH-asymmetric integrated cell, combining CO₂ reduction and 5-hydroxymethylfurfural oxidation, produces 2,5-furandicarboxylic acid and formate with high yields (around 90.0%).

Fenghui Ye, Shishi Zhang, Qingqing Cheng, Yongde Long, Dong Liu, Rajib Paul, Yunming Fang, Yaqiong Su, Liangti Qu, Liming Dai, Chuangang Hu