Recent trends, advances, and challenges in MOF-derived metal oxide semiconductor-based sensors for BTEX detection: A review

The precise monitoring of extremely deadly volatile organic compounds based on aromatic hydrocarbons such as benzene, toluene, ethylbenzene, and xylene (BTEX) is desired for indoor air quality. Due to their unique morphology, tunable architectures, mesoporous structure, and compositions, metal-organic frameworks (MOFs) have attracted substantial interest in the fabrication of ultra-sensitive and selective-based gas sensors. This is because of their exceptional characteristics, like specific adsorption affinities, vastly diversified structures, bulky surface area, and functionalized sites. Thus, the current review reports on the recent developments in the design, synthesis, and properties of MOF-derived semiconductor metal oxides (SMOs). Moreover, the fabrication of MOFderived SMO-based sensors for monitoring toxic vapours, such as BTEX compounds, for environmental and air quality applications is also discussed. The gas sensing mechanisms associated with BTEX detection are also highlighted in detail. It further deliberates on the advances in MOF-derived SMO-based sensors for their integration in smartphones, the Internet of Things (IoT), and self-powered sensors to pave the way for cost-efficient and portable monitoring of BTEX. This review concludes by summarizing accomplishments and current challenges, delivering a forthcoming viewpoint for the advancement of next-generation MOF-based sensors in realworld environments.