Carbon felt by acid treatment as highly active metal-free electrocatalyst for selective hydrogenation of cinnamaldehyde to hydrocinnamaldehyde

Abstract

Carbon felt by concentrated nitric acid treatment (CFn) was utilized directly as metal-free electrode for electrochemical hydrogenation of cinnamaldehyde (CAL) for the first time. CFn shows high selectivity and Faradaic efficiency (FE) in converting CAL to hydrocinnamaldehyde (HCAL). At a constant current density of 20 mA·cm-2, CFn achieved 81.5% selectivity to HCAL with a FE of 85.7%. Compared with pristine carbon felt (CF), CFn has more π electrons and carbonyl groups on its surface which facilitate the adsorption of CAL and H2O, and larger electrochemical surface area and good electron transfer property. These may be responsible for its excellent performance for selective hydrogenation of CAL to HCAL. This work provides a cost-effective metal-free catalyst for HCAL production.