Room-temperature ammonia gas sensing via Au nanoparticle-decorated TiO2 nanosheets

Abstract

A high-performance gas sensor operating at room temperature is always favourable since it simplifies the device fabrication and lowers the operating power by eliminating a heater. Herein, we fabricated the ammonia (NH3) gas sensor by using Au nanoparticle-decorated TiO2 nanosheets, which were synthesized via two distinct processes: (1) preparation of monolayer TiO2 nanosheets through flux growth and a subsequent chemical exfoliation and (2) decoration of Au nanoparticles on the TiO2 nanosheets via hydrothermal method. Based on the morphological, compositional, crystallographic, and surface characteristics of this low-dimensional nano-heterostructured material, its temperature- and concentration-dependent NH3 gas-sensing properties were investigated. A high response of ~ 2.8 was obtained at room temperature under 20 ppm NH3 gas concentration by decorating Au nanoparticles onto the surface of TiO2 nanosheets, which generated oxygen defects and induced spillover effect as well.

Low ppm NO2 detection through advanced ultrasensitive copper oxide gas sensor

“…Metal oxides are currently being extensively researched in the gas-sensing field because of their semiconducting properties, high sensitivity and ease of measurement [14]. Although there have been advancements in gas detection technology but many commercial products still rely on n-type semiconductors sensing materials like ZnO, In 2 O 3 , Fe 2 O 3 , SnO2, TiO 2 and WO 3 for detecting hazardous gases [15,16]. The information on application of p-type metal oxide semiconducting materials for gas-sensing is limited [17].…”