La-doped CeO2 nanoflowers catalysts for direct synthesis of dimethyl carbonate from CO2 and methanol

Abstract

The catalytic direct synthesis of dimethyl carbonate (DMC) from CO₂ and methanol is a crucial approach to utilizing CO₂ and producing high-value chemicals. However, the high stability of the CO₂ molecule imposes thermodynamic limitations on this reaction pathway, along with challenges related to insufficient catalyst activity and stability. Currently, solutions primarily focus on developing efficient catalyst. Herein, La-doped CeO₂ nanoflower catalysts (La_xCeO₂) were synthesized via hydrothermal method. Characterization reveals that La doping optimizes the pore structure and enriched oxygen vacancies, thereby enhancing catalytic performance. Notably, La_0.1CeO₂ exhibits the largest pore size and highest oxygen vacancy content, achieving a remarkable DMC productivity of 9.42 mmol/g under 140 °C, 4 MPa of CO₂, and 3 h of reaction, surpassing pure CeO₂ nanoflowers. Based on experimental findings and in-situ diffuse infrared Fourier transform analysis, a plausible reaction pathway was proposed. This work underscores the potential of La_xCeO₂ nanoflowers as efficient catalysts for sustainable CO₂ conversion to DMC.