Electrical and sensitivity properties of ZnO/TiO2 heterojunction nanocomposites for ammonia gas sensor

Abstract

The ZnO/TiO2 heterojunction nanocomposites were synthesized via a thermal process. The morphology of the samples showed TiO2 nanoparticles with rang of 50-100 nm in diameter and ZnO nanoparticles with size of upper than 100 nm. The XRD patterns of ZnO/TiO2 nanocomposites indicate ZnO, anatase, and rutile phases. The current-voltage characteristics of ZnO and TiO2 nanoparticles, and ZnO/TiO2 heterojunction nanocomposites show behaviour of ohmic contact materials. The material sensitivity was measured under an ammonia atmosphere for 200 seconds at room temperature. The results showed maximum response of ZnO/TiO2 nanoparticles with 27.30 for 200 seconds.