Zr doping on CeO₂ nanocube catalysts to enhance oxygen storage capacity for Water-Gas shift reaction

Zr was doped on Co/CeO₂ cubic catalysts to enhance oxygen storage capacity (OSC) in the water–gas shift (WGS) reaction using waste-derived synthesis gas. Zr concentrations (0, 0.22, 1.86, and 7.01 wt%) were changed systemically to see the effect of Zr on OSC. The analysis of the characteristics reveals that the newly synthesized catalysts demonstrate superior OSC compared to the CeO₂ supported Co catalyst previously developed by our lab. The catalyst with the highest Zr content (7.01 wt%) demonstrated substantial carbon monoxide conversion after 50 h, highlighting the critical role of OSC in catalytic WGS stability. Conversely, a minimal Zr addition (0.22 wt%) resulted in the highest initial catalytic activity, which was attributed to an above-average Brunauer–Emmett–Teller surface area, Co dispersion, and relatively sufficient OSC. The findings emphasize that Zr doping considerably enhances the OSC of Co/CeO₂ cubic catalysts, which is essentially linked to catalytic performance such as stability and activity. These insights confirm that precise Zr doping is a crucial strategy for modulating OSC, thereby enhancing the physicochemical properties of catalysts for improved efficiency in environmental and industrial applications, particularly in WGS reactions.