Insights into nano-heterostructured materials for gas sensing: a review

Highly sensitive and selective gas sensors with low energy consumption amenable to miniaturization are required for real-time monitoring applications. The challenge is produce sensing units at a sufficiently cost allow broad deployment, which can only be reached efficient materials fabrication procedures. In this context, metal oxides promising next-generation due their high surface-area-to-volume ratio, electron transfer, enhanced tunable surface reactivity, fast response, short recovery time. However, from normally not have operated temperatures. These limitations been overcome strategies such as doping other oxides, UV-illumination, noble decoration. This review concentrates on the design mechanisms of heterostructures sensors, obtained in conjunction (e.g. 2D materials). key topics discussed include: (a) synthesis oxide (MOHs); (b) semiconducting comprising n–n, n–p, p–p heterojunctions, emphasis mechanisms; (c) produced involving materials. challenges prospects based MOHs also discussed.