A highly sensitive and fast-responding ethanol sensor based on CdIn2O4 nanocrystals synthesized by a nonaqueous sol-gel route

CdIn2O4 nanoparticles with crystallite sizes of about 10 nm were obtained by a nonaqueous sol-gel route involving the reaction of cadmium acetate and indium isopropoxide in benzyl alcohol. Without the use of any additional stabilizing agents, the crystal growth is restricted by the solvent and/or by the organic reaction products. The as-fabricated sensor showed high response, fast response, and recovery times toward ethanol gas. The performance of a home-built Cdln(2)O(4) nanocrystal sensor was even better than the competing SnO2 and In2O3 sensors, making this material not only interesting for sensor devices, but also for a number of related electrochemical applications.