Ionic liquid-supported synthesis of CeO2 nanoparticles and its enhanced ethanol gas sensing properties

Abstract

Reducing the particle size of ceria nanostrutures could provide an efficient approach to improve gas sensing properties thereof. Here, we synthesized small CeO2 nanoparticles (3-5 nm) in the support of [EMIM][Tf2N] ionic liquid. The obtained CeO2 nanoparticles showed relatively large surface areas (68.29m(3)/g) and especially high content of Ce3+ ions (13.5%), which increase the chemisorption of reagents and oxygen leading on enhancing gas sensing performance. Namely, at the optimal operating temperature of 400 degrees C, the gas response of synthesized CeO2 sensor to 100 ppm of ethanol was 2.3, which was 1.83 times higher than that of commercial one (1.26). The superior gas sensing mechanism of synthesized CeO2 was also discussed on the basis of the electrical resistance change. The present work could provide novel pathway to synthesize ceria and related materials, which would be possibly expected to be potential candidates for gas sensing, by the use of ionic liquid hereafter.