Operando mechanistic studies of selective oxidation of glycerol to dihydroxyacetone over amorphous cobalt oxide

In this work, cobalt oxide (CoOx) has been demonstrated as an efficient and selective electrocatalyst for producing value-added dihydroxyacetone (DHA) from industrial by-product glycerol. Under optimized conditions, DHA with high selectivity up to 45% and a high production rate of 9.6 mu mol h-1 cm-2 is obtained at high current density over 3 mA cm-2 without the occurrence of the oxygen evolution reaction. Operando Raman spectroscopy features the potential-induced structural transformation between CoOx and oxyhydroxides from which a correlation among applied potential, surface chemistry of electrocatalyst, and product distribution are built. These results point toward the viability of using inexpensive materials for electrochemical biomass upgrading as well as providing opportunities for studying structural evolution and activity origin of catalysts under realistic working conditions that can be widely extended to most electrocatalytic biomass valorization processes.