A photoactivated gas detector for toluene sensing at room temperature based on new coral-like ZnO nanostructure arrays
Journal
Sensors (Switzerland)
Journal Volume
16
Journal Issue
11
Date Issued
2016
Author(s)
Yeh, L.-K.
Luo, J.-C.
Chen, M.-C.
Wu, C.-H.
Chen, J.-Z.
Cheng, I.-C.
Hsu, C.-C.
Tian, W.-C.
WEI-CHENG TIAN
Abstract
A photoactivated gas detector operated at room temperature was microfabricated using a simple hydrothermal method. We report that the photoactivated gas detector can detect toluene using a UV illumination of 2 μW/cm². By ultraviolet (UV) illumination, gas detectors sense toluene at room temperature without heating. A significant enhancement of detector sensitivity is achieved because of the high surface-area-to-volume ratio of the morphology of the coral-like ZnO nanorods arrays (NRAs) and the increased number of photo-induced oxygen ions under UV illumination. The corresponding sensitivity (ΔR/R₀) of the detector based on coral-like ZnO NRAs is enhanced by approximately 1022% compared to that of thin-film detectors. The proposed detector greatly extends the dynamic range of detection of metal-oxide-based detectors for gas sensing applications. We report the first-ever detection of toluene with a novel coral-like NRAs gas detector at room temperature. A sensing mechanism model is also proposed to explain the sensing responses of gas detectors based on coral-like ZnO NRAs.
SDGs
Type
journal article