CO2 Self-Poisoning and Its Mitigation in CuO Catalyzed CO Oxidation: Determining and Speeding up the Rate-Determining Step

Cu-based catalysts are promising for CO oxidation applications with catalyst deactivation being a major barrier. We start CuO/Al2O3 and find that while the conversion decreases, CO2 accumulates average Cu chemical state stays same. It suggests self-poisoning, i.e., desorption is rate-determining step. Subsequently, experiments performed to prove this hypothesis by showing (1) adsorption inhibits O2 adsorption, (2) complete of regenerate catalyst, (3) pre-adsorbed quenches activity which recovers during reaction (4) apparent activation energy consistent desorption. further evidenced using stronger adsorbing support CeO2 speed up from CuO sites resulting in superior CuO/CeO2 catalyst. provides an example experimentally deciding speeding step catalytic reaction.