ZnO-SnO2 heterojunction nanobelts: Synthesis and ultraviolet light irradiation to improve the triethylamine sensing properties

ZnO-SnO2 heterojunction nanobelts with hollow interiors are successfully designed and synthesized using a facile two-step method. The as-synthesized ZnO-SnO2 heterojunction nanobelts are used for the detection of the highly toxic and pungent volatile organic compound triethylamine (TEA). The sensing properties of the as-fabricated sensor under ultraviolet (UV) laser illumination are carefully investigated and the results exhibit fast response/recovery times, good sensitivity and superior repeatability with regard to the TEA detection. Specifically, the ZnO-SnO2 sensor exhibits a faster response speed (1.8 s) and recovery speed (18 s) under UV illumination conditions. The UV laser enhanced sensing mechanism of the heterojunction nanobelts is also discussed.