That dimethyl carbonate is directly synthesized from methanol and carbon dioxide is an effective and environmental approach to solve the greenhouse effect. For the sake of solving the problems of low DMC productivity and poor catalysts stability in presence of the formed water. Here we design and prepare a serial of spherical La-doped ceria nanoparticles (Ce_(1-x)La_xO_ nanocomposites, x=0.00, 0.05, 0.10, 0.15, and 0.20) via a co-precipitation method. These Ce_(1-x)La_xO_ composites are ground into slurry by ball milled and then coated on cordierite honeycomb ceramics to obtain Ce_(1-x)La_xO_ monolithic catalysts. These Ce_(1-x)La_xO_ composites are characterized extensively by TEM, XRD, Raman spectroscopy, N_2 adsorption-desorption isotherms, H_2-TPR and XPS. The characterization results show that the Ce_(1-x)La_xO_ composites nanoparticles possesses richer surface oxygen vacancies, higher BET surface area and smaller particle size than that of pure CeO_2 nanoparticle. Besides, catalytic activity test shows these Ce_(1-x)La_xO_ monolithic catalysts exhibit better catalytic performance than that of pure CeO_2 nanoparticles. Among them, Ce_(0.95)La_(0.05)O_ monolithic catalyst exhibits the highest CH3OH conversion and DMC yield, which is in good line with the oxygen vacancy content measured by XPS. Finally, the Ce_(0.95)La_(0.05)O_ monolithic catalyst also shows an excellent durability of more than 100 hours, which is mainly due to the doping effect of lanthanum into the ceria oxides tailoring the structure and surface properties of the catalyst.
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