Overcoming the Deactivation of Pt/CNT by Introducing CeO<sub>2</sub> for Selective Base-Free Glycerol-to-Glyceric Acid Oxidation
Xueqiong Zhang, Dan Zhou, Xiaojing Wang, Jian Zhou, Jiefei Li, Mingkai Zhang, Yihong Shen, Haibin Chu, Yongquan Qu
Abstract
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.