The detection and monitoring of harmful and toxic gases have become increasingly important due to global environmental concerns. Semiconducting metal oxide gas sensors are promising tools for the remote detection of gases and vapors. However, achieving the necessary sensitivity, selectivity, stability, and response/recovery rates for practical applications remains challenging. Recent research has focused on developing novel sensing materials with unique architectures and fabrication processes. One promising approach is the creation of ordered macroporous metal oxide nanostructures with pore sizes ranging from 50 nm to 1.5 μm, which enhance chemical diffusion rates and improve performance stability and repeatability. This review highlights the latest advancements in fabricating these nanostructures, examining how their structural layouts, hierarchies, doping, and heterojunctions influence sensing behavior. It also discusses future prospects, providing guidelines for optimizing the sensing performance of porous materials through specific component and structural design.-Scientific Journal cover design by scapiens

https://pubs.rsc.org/en/content/articlelanding/2019/na/c8na00303c#!divAbstract