Controllable synthesis of nano-CeO2 by the hydrothermal route and its effect on the activity of CO2 non-reductive transformation

Abstract

The catalytic conversion of CO₂ and diols to polycarbonates is conducive to the construction of a sustainable carbon source, but its efficiency largely depends on the catalysts. In this study, CeO₂ catalysts with different sizes and morphologies were synthesized via hydrothermal methods. The effect of CeO₂ morphology (nanoparticles, nanorods, and nanocubes) on this reaction was further investigated. Precise control of nano-CeO₂ morphology altered the surface Ce⁴⁺/Ce³⁺ ratio, inducing surface defects and enhancing catalytic activity. Among the tested morphologies, CeO₂ nanorods exhibited the highest catalytic performance (diol conversion > 90.5%, polycarbonate selectivity > 89.3%) and stability. The exposed (110) and (100) planes of CeO₂ increased oxygen vacancy concentrations and strengthened CO₂ interactions, promoting bicarbonate and bidentate carbonate formation on the CeO₂ surface and thereby enhancing CO₂ non-reductive transformation activity.