High-Surface Area Mesoporous Sc 2 O 3 with Abundant Oxygen Vacancies as New and Advanced Electrocatalyst for Electrochemical Biomass Valorization.

Scandium oxide (Sc 2 O 3 ) is considered as omnipotent "Industrial Ajinomoto" and holds promise in catalytic applications. However, rarely little attention is paid to its electrochemistry. Here, the first nanocasting design of high-surface area Sc 2 O 3 with abundant oxygen vacancies (mesoporous V O -Sc 2 O 3 ) for efficient electrochemical biomass valorization is reported. In the case of the electro-oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA), quantitative HMF conversion, high yield, and high faradic efficiency of FDCA via the hydroxymethylfurancarboxylic acid pathway are achieved by this advanced electrocatalyst. The beneficial effect of the V O on the electrocatalytic performance of the mesoporous V O -Sc 2 O 3 is revealed by the enhanced adsorption of reactants and the reduced energy barrier in the electrochemical process. The concerted design, in situ and ex situ experimental studies and theoretical calculations shown in this work should shed light on the rational elaboration of advanced electrocatalysts, and contribute to the establishment of a circular carbon economy since the bio-plastic monomer and green hydrogen are efficiently synthesized.