Improved triethylamine sensing properties by designing an In2O3/ZnO heterojunction

Made available in DSpace on 2022-04-28T19:47:55Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-11-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Sensors of volatile organic compounds (VOCs) play a vital role in environmental monitoring. Although much progress has been made to develop new sensing materials, it remains challenging to detect a particular VOC selectively and without the interference of humidity. Herein, we report the effect of In2O3 nanoparticles on the VOC-sensing performance of ZnO twin-rods. The VOC-sensing tests were carried out in dry air and at a relative humidity (RH) of 26, 59, and 98%. The results indicated that the In2O3/ZnO heterostructure exhibited an improved sensing performance to triethylamine (TEA) compared to ZnO. In dry air, the responses to 100 ppm of TEA at 350 °C were 60.2 for the In2O3/ZnO heterostructure and 39.2 for pure ZnO. In2O3/ZnO even exhibited a high response of 6.2 to 1 ppm of TEA. Moreover, In2O3/ZnO exhibited a response to TEA up to 46.2 times higher than those of the other VOCs, indicating excellent selectivity. At 98% RH, the In2O3/ZnO heterostructure still had a high sensitivity to TEA, showing a response of 21.2 to 100 ppm of TEA with a response time of 1 s. The improved TEA-sensing performance of the In2O3/ZnO heterostructure can be attributed to the formation of the n-n heterojunction. Laboratory of Materials for Sustainability (LabMatSus) Ibilce São Paulo State University (Unesp), R. Cristóvão Colombo, 2265 Laboratory of Materials for Sustainability (LabMatSus) Ibilce São Paulo State University (Unesp), R. Cristóvão Colombo, 2265 FAPESP: 2016/25267-8 FAPESP: 2017/01267-1 FAPESP: 2018/00033-0 FAPESP: 2018/01258-5 FAPESP: 2019/12345-9 FAPESP: 2020/06421-1 CNPq: 308327/2018-7