ZnO Nano/Microwires Ethanol Sensors: Role of TiO2 Additive

Theerapong Santhaveesuk; Supab Choopun

doi:10.55674/ias.v15i3.268724

Authors

Theerapong Santhaveesuk Physics Program, Faculty of Science and Technology, Sakon Nakhon Rajabhat University, Sakon Nakhon, 47000 Thailand. https://orcid.org/0000-0003-1083-4247
Supab Choopun Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand.

DOI:

https://doi.org/10.55674/ias.v15i3.268724

Keywords:

Nanostructured materials, Thermal oxidation, Additive, Gas sensor, ZnO

Abstract

ZnO nano/microwires (ZnO-NMWs) with varying TiO₂ additions (0 − 30 mol% TiO₂) were synthesized at temperatures ranging from 600 − 800°C for 12 h via a simple thermal oxidation reaction method in a normal atmosphere. The characterizations of the ZnO-NMWs were carried out, and it was found that the greatest quantity and longest ZnO-NMWs were observed at a heating temperature of 600°C. The heating temperature significantly influenced the quantity and dimensions of the ZnO-NMWs. The formation of the fcc-Zn₂TiO₄ phase was distinctly identified using XRD and Raman analyses, and an increased proportion of the Zn₂TiO₄ phase was achieved with elevated heating temperatures. The ZnO-NMWs, synthesized at 600°C with varying TiO₂ additives, were applied as ethanol sensors, and their ethanol sensing properties were investigated. An improvement of sensor response due to TiO₂ addition can be attributed to the reduction in electron concentration within the sensor, resulting from the formation of Zn₂TiO₄ phase. The NWs-TiZnO-30 sensor shows the highest sensing response of 9.30 at 360°C. Consequently, the incorporation of TiO₂ with ZnO-NMWs is a promising method for improving sensor response.

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