Solution-processed CuO/TiO₂ heterojunction for enhanced room temperature ethanol sensing applications

Low-temperature solution techniques were employed to synthesize a hetero-junction sensor based on TiO₂ nanorod arrays functionalized with CuO nanoparticles and its room temperature (29 °C) ethanol sensing characteristics were investigated. The structural, optical, morphological and electrical properties of the samples were analyzed using various characterization techniques. Both TiO₂ nanorod array as well as CuO/TiO₂ heterojunction exhibit room temperature ethanol sensing performance and the heterojunction sensor shows excellent response characteristics compared to pristine TiO₂. The enhanced response can be attributed to the increased specific surface area and the formation of the p-n heterojunction. The room temperature sensing properties makes the heterojunction sensor a promising candidate for environmental monitoring. (paper)