Enhancing the surface area stability of the cerium oxide reverse water gas shift nanocatalyst via reverse microemulsion synthesis

High surface area cerium oxide was synthesized via the reverse microemulsion method and assessed for CO₂ reduction to CO via reverse water gas shift. The resulted ceria nanoparticles (ca. 4 nm) were 100% selective to CO formation, while attaining a nearly equilibrium CO₂ conversion at 600 °C. As compared to ceria synthesized by wet precipitation, the reverse microemulsion-synthesized ceria exhibited enhanced surface stability and a more stable catalytic performance (declining from 63% to 50% over 100 h on stream). No significant carbon formation was detected and a relatively small decline in conversion was related to the specific surface area reduction induced by the growth of ceria nanoparticles under the reaction conditions.