Premium
Room‐Temperature NO 2 Gas Sensing with Ultra‐Sensitivity Activated by Ultraviolet Light Based on SnO 2 Monolayer Array Film
Author(s) -
Liu Bo,
Luo Yuanyuan,
Li Ke,
Wang Hong,
Gao Lei,
Duan Guotao
Publication year - 2019
Publication title -
advanced materials interfaces
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.671
H-Index - 65
ISSN - 2196-7350
DOI - 10.1002/admi.201900376
Subject(s) - monolayer , materials science , ultraviolet , adsorption , irradiation , optoelectronics , selectivity , ultraviolet light , explosive material , nanotechnology , chemical engineering , photochemistry , chemistry , organic chemistry , physics , nuclear physics , engineering , catalysis
Chemiresistive‐type gas sensors, which are driven by the thermal activation, have exhibited extraordinary promise for the detection of air pollutions, such as highly toxic gas of nitrogen dioxide (NO 2 ), but are often limited to its high operating temperature, because of the raising explosive risk in inflammable gases. This study reports the construction of a close‐packed SnO 2 monolayer film, and uses it as the NO 2 room‐temperature sensing layer induced by ultraviolet (UV)‐light irradiation. Such SnO 2 monolayer array film shows excellent sensing performances toward NO 2 gas with a striking selectivity under the UV‐light irradiation even in high humidity. Additionally, by precisely controlling the sensing film thickness, it is observed that the NO 2 sensing characteristics can be optimized to provide ultra‐selectivity and high gas response. Through the systematic analysis, it reveals that the “clean effect” of UV‐light for surface‐adsorbed O 2 b− ions and the competitive adsorption between NO 2 and O 2 gas during sensing process are responsible for the possible sensing mechanism. More importantly, this work exhibits the intrinsic relation between sensing performances and the film thickness under the UV‐light illumination, which is of vital importance to actual sensing requirements.