Synthesis of WO_3 and its gas sensing: a review

摘要

As a typical n-type semiconductor, WO_3 is considered to be the promising material to fabricate the gas sensor, which has a widespread utilization in the environment detecting and the safety monitoring. This review details the different structures of WO_3 synthesized in recent studies, classifying them into five sections according to their dimensionality, then elucidates the research progress of the gas sensitivity towards H_2, CO, H_2S, NH_3, NO_x, O_3 as well as some organic gases, based on which two models are proposed to explain the corresponding gas sensing mechanisms. Besides these, some unsolved problems and possible future directions are also discussed.