Numerous methodologies have been developed for the synthesis of cerium oxide or ceria, a commercially important lanthanide oxide. Some of the techniques employ long reaction times, elevated temperatures and/or pressures, expensive metal alkoxides and caustic alkalis. This necessitates the need to develop milder, environment friendly synthetic routes for cerium oxide generation. Herein, we report a rapid, room temperature methodology to synthesize fluorite-structured ceria nanoparticles using cerium (III) salts and ozone in the presence of short chain primary, secondary, and tertiary alcohols. This simple technique produced nanoparticles with higher oxygen vacancy compared to that of bulk ceria. Chemical species in the reaction mixtures were studied to elucidate a possible growth mechanism of these nanoparticles from ozonating alcoholic solutions of cerium salts. The catalytic activity of ceria nanoparticles towards the oxidation of carbon monoxide (CO) was further evaluated and compared with that of commercial bulk ceria.