Recent Research Trends for Metal Oxide Nanostructures Based Chemoresistive Gas Sensors

Abstract

In the modern era, advanced industrial and process technologies in various fields are known to produce harmful gases. These gases typically leak at low concentrations, but continuous exposure can cause serious harm to health and safety. Since human sensory organs cannot detect these risks or leaking hazardous gases, there has been significant interest in developing high-performance gas sensors capable of rapidly detecting harmful and hazardous gas leaks. Metal oxides possess several advantages for such applications, including ease of manufacturing, affordability, and high sensitivity to harmful gases. In this review, we highlight recent progress in the field of chemo-resistive gas sensors based on metal-oxide nanostructures. It begins by discussing the features of various nanostructure morphologies such as 0-dimensional nanospheres to nanocomposites of nanowires. It then describes methods for fabricating metal-oxide nanostructures. Finally, we describe recent advances in the design and fabrication of nanostructures for metal-oxide gas sensors using four different morphologies: 0-dimensional (0 D, nanosphere and nanoparticle), 1-dimensional (1 D, nanowire and nanorod), 3-dimensional (3 D, nanoflower and nanocomposite), and heterojunctions. Based on their morphology-dependent sensing properties, there are various fields of application for gas sensors, with different target gases. This review can serve as an overview of recent research trends and offer insights into the future development of next-generation high-performance gas sensors.