Overcoming the Deactivation of Pt/CNT by Introducing CeO₂ for Selective Base-Free Glycerol-to-Glyceric Acid Oxidation

Catalytic base-free oxidation of biomass-derived glycerol represents a promising approach for the value-added utilization of glycerol. However, the commonly used Pt/carbon nanotubes (Pt/CNT) catalysts suffer from the severe deactivation, because of the strong adsorption of glyceric acid (GLYA), resulting in the serious Pt-surface poisoning and their consequent poor activity with low selectivity toward GLYA. Here, we demonstrate that integrating CeO₂ with Pt/CNT could effectively alleviate the catalyst deactivation, delivering high activity and selectivity to produce GLYA. The valence band analysis and kinetic experiments suggest that the Pt-CeO₂/CNT ternary interface would weaken the GLYA adsorption on Pt and lower the energy barrier for glycerol oxidation. Moreover, via the generated OH* from H₂O dissociation, CeO₂ can promote the oxidation of primary hydroxyl groups of glycerol, leading to a high selectivity of GLYA.