Porous In2O3-ZnO nanofiber-based sensor for ultrasensitive room-temperature detection of toluene gas under UV illumination

Toluene gas is hazardous but plays a vital role in several industries. Hence, the detection of toluene gas is important for human health and the environment. In this study, porous In2O3-ZnO nanofibers were prepared via a facile electrospinning method to fabricate a toluene gas sensor. Illumination by ultraviolet light (365 nm) was used to realize the room temperature (RT) operation of the fabricated sensor. The structural properties of the sensor were studied using various characterization techniques. The prepared nanofibers consisted of many subnanograins, particularly ZnO and In2O3, and contained numerous pores in-between the nanograins. Consequently, these nanofibers had a large surface area, increasing the probability of contact between the gas and sensor. The prepared sensors were functional at RT under UV illumination and showed excellent toluene-sensing properties. The porous In2O3- appended ZnO-nanofiber-based sensors showed more stable and sensitive response curves than those of the pure ZnO nanofiber-based sensor. Moreover, In2O3-appended ZnO nano fiber sensors could only faintly detect other gases, such as NO2, acetone, ethanol, H2S, and CO gases, indicating that the sensor exhibits highly selective toluene sensing. & COPY; 2023 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Automated summary

In this study, porous In2O3-ZnO nanofibers were prepared via electrospinning method to fabricate a toluene gas sensor. The sensor could operate at room temperature with the illumination of ultraviolet light (365 nm). The structural properties of the sensor were characterized, and it was found that the nanofibers consisted of subnanograins with numerous pores, resulting in a large surface area for increased gas-sensor contact. The sensor showed excellent toluene-sensing properties with high selectivity.