A Gas Sensor Based on Network Nanowire for H₂S Monitor in Construction Waste Landfill

• Main Authors: Pengyu Ren, Qingwei Shi, Lingling Qi
• Format: Article
• Language: English
• Published: MDPI AG 2021-06-01
• Series: Chemosensors
• Subjects: network nanowires; nanorod; construction waste landfill; H₂S gas
• Online Access: https://www.mdpi.com/2227-9040/9/7/156

As an extremely harmful gas, H₂S gas is the major pollutant in construction waste landfill. Herein, a one-dimensional oxide nanomaterial was produced from a simple wet chemical method to serve as a H₂S gas sensing material. The SEM observation indicates that the nanomaterial with network structure is constructed by a lot of nanowires with an approximate diameter from 24 nm to 40 nm. The sensing film was formed on a ceramic substrate using a slurry composed of the as-prepared network nanowires. Furthermore, a gas sensing measurement was carried out to determine the gas sensing performances towards the H₂S gas. The detection results at different working temperature towards various gas concentrations demonstrate that the network nanowires-based sensor exhibits a higher gas response to H₂S as compared to that of the rod-like one. The optimum working temperature of the network and rod-like nanomaterials is both 300 °C, and the corresponding maximum gas response is 24.4 and 13.6, respectively. Namely, the gas response of the network-based gas sensor is almost larger than that of the rod-like oxide. Moreover, the network nanowires-based gas sensor display a faster gas response and recovery speed. In addition, the fabricated gas sensors all exhibit excellent repeatability. Such improved sensing properties may offer a promising potential to realize an efficient detection of harmful H₂S gas released from construction waste landfill.