Insights into reverse oxygen spillover effect induced via CeO2 modulation to enhance the stability of CuCoOx catalysts in hydrodeoxygenation of biomass derivatives.

In hydrodeoxygenation (HDO) reactions, the evolution of the chemical states of active species in the catalyst caused by the spillover effects greatly influences their catalyst performance. Herein, the HDO of guaiacol (GUA) over CuCoO x and CuCoCeO x catalysts synthesized by co-precipitation method was systematically investigated. During the HDO reaction of GUA, acid sites (Co(II)) facilitated the C-O bond (demethylation via -OCH 3) cleavage, which was the rate-determining step. A series of characterizations and experimental results revealed that introducing CeO 2 into the CuCoO x catalyst could enable the catalyst to undergo reverse oxygen spillover in the hydrogenation environment, promoting the regeneration of CoO in the catalyst. Therefore, the deactivation of the CuCoO x catalyst due to hydrogen spillover and CoO reduction could be avoided, and the catalyst stability improved. The present study methodically investigated the spillover effects induced by Cu and CeO 2 and provided the theoretical basis for the structural design of heterogeneous catalysts. [Display omitted] • Guaiacol HDO reaction with C-O bond scission as the rate-determining step. • Construction of CuCoO x -based catalysts with acid sites (Co(II)) as active center. • Utilization of reverse oxygen spillover to improve CuCoO x catalyst stability. • Catalyst deactivation and stability mechanisms discussed based on spillover effects. [ABSTRACT FROM AUTHOR]