Preparation and Application of TiO2 Nanotube Array Gas Sensor for SF6-Insulated Equipment Detection: a Review

摘要

Since Zwilling and co-workers first introduced the electrochemical anodization method to prepare TiO~(2) nanotubes in 1999, it has attracted a lot of researches due to its outstanding gas response and selectivity, making it widely used in gas detection field. This review presents an introduction to the sensor applications of TiO~(2) nanotube arrays (TNTAs) in sulfur hexafluoride (SF~(6))-insulated equipment, which is used to evaluate and diagnose the insulation status of SF~(6)-insulated equipment by detecting their typical decomposition products of SF~(6): sulfur dioxide (SO~(2)), thionyl fluoride (SOF~(2)), and sulfuryl fluoride (SO~(2)F~(2)). The synthesis and sensing properties of TiO~(2) nanotubes are discussed first. Then, it is followed by discussing the theoretical sensing to the typical SF~(6) decomposition products, SO~(2), SOF~(2), and SO~(2)F~(2), which analyzes the sensing mechanism at the molecular level. Finally, the gas response of pure and modified TiO~(2) nanotubes sensor to SO~(2), SOF~(2), and SO~(2)F~(2) is provided according to the change of resistance in experimental observation.