The Lewis Acid–Base Microenvironment-Induced Confinement of the Host Metal in Pd/Ce-MOF Drives Glycerol Carbonate Synthesis

Abstract

Pd/Ce-MOF has demonstrated exceptional potential as a highly efficient catalyst for the oxidative carbonylation of glycerol. Its superior catalytic performance, significantly surpassing that of Pd/Zn-MOF and Pd/Cu-MOF, is primarily attributed to the abundant Lewis acid–base pairs, which create a favorable microenvironment for electron transfer between the host and guest metals. This synergistic interaction enhances electron mobility, facilitating the efficient desorption of reactive intermediates. Furthermore, the induced confined anchoring process ensures highly dispersed and stable active sites, enabling Pd/Ce-MOF to maintain superior catalytic performance during glycerol carbonate synthesis. Under optimized conditions of 140 °C, 4 MPa, and 0.6% Pd confined immobilization amount, the catalyst achieved an impressive yield of 91.7% and a selectivity of 97.9% within 2 h, demonstrating both excellent efficiency and cost-effectiveness. Additionally, its stability was confirmed through repeated experiments, with the yield remaining at approximately 81% even after five cycles. Experimental results and theoretical calculations indicate that the strong host–guest metal interaction between Pd and Ce-MOF significantly reduces CO adsorption energy, thereby reducing the reaction activation energy and boosting catalytic activity.