Densely populated mesopores in microcuboid CeO₂crystal leading to a significant enhancement of catalytic activity

Abstract

Unique mesoporous microcuboid CeO2 crystals were prepared by a facile method, involving the hydrothermal hydrolysis of a Ce(NO3)3 aqueous solution in the presence of urea at 180 °C followed by calcination at 400 °C, and characterized with XRD, SEM, TEM, BET, Raman, XPS, positron annihilation spectroscopy and TPR. It was found for the first time that the presence of densely populated mesopores in the microcuboid CeO2 crystals results in highly reactive surface lattice oxygen due to the exposure of the mesopore wall surface with high interfacial curvature, thus leading to a significant enhancement in catalytic activity as compared to single crystal CeO2 nanocubes without mesopores.