Review—Recent Development of WO ₃ for Toxic Gas Sensors Applications

WO ₃ -based gas sensors have attracted the attention of researchers around the world in creating and developing sensors that are sensitive, stable, and have excellent reproducibility against harmful gases. Various studies that have been performed since the last few years exhibited the superior potential of WO ₃ in carrying out optimal chemisorption of oxidizing and reducing gas molecules. The additional materials such as metal, metal oxide, and carbon nanomaterial can significantly widen the active state area of the WO ₃ surface and other facts in various studies illustrate that the addition of polymers will change the characteristics of the semiconductor sensor. This review provides a comprehensive review of the development and modification of WO ₃ for enhancing toxic gas sensor performances. In addition, the discussion of the sensing mechanism, future opportunities as well as challenges will be addressed thereby can inspire research progress on WO ₃ -based toxic gas detection sensors.