title: Metal-oxide-semiconductor based gas sensors: screening, preparation, and integration.
abstract: Metal-oxide-semiconductor (MOS) based gas sensors have been considered a promising candidate for gas detection over the past few years. However, the sensing properties of MOS-based gas sensors also need to be further enhanced to satisfy the higher requirements for specific applications, such as medical diagnosis based on human breath, gas detection in harsh environments, etc. In these fields, excellent selectivity, low power consumption, a fast response/recovery rate, low humidity dependence and a low limit of detection concentration should be fulfilled simultaneously, which pose great challenges to the MOS-based gas sensors. Recently, in order to improve the sensing performances of MOS-based gas sensors, more and more researchers have carried out extensive research from theory to practice. For a similar purpose, on the basis of the whole fabrication process of gas sensors, this review gives a presentation of the important role of screening and the recent developments in high throughput screening. Subsequently, together with the sensing mechanism, the factors influencing the sensing properties of MOSs involved in material preparation processes were also discussed in detail. It was concluded that the sensing properties of MOSs not only depend on the morphological structure (particle size, morphology, pore size, etc.), but also rely on the defect structure and heterointerface structure (grain boundaries, heterointerfaces, defect concentrations, etc.). Therefore, the material-sensor integration was also introduced to maintain the structural stability in the sensor fabrication process, ensuring the sensing stability of MOS-based gas sensors. Finally, the perspectives of the MOS-based gas sensors in the aspects of fundamental research and the improvements in the sensing properties are pointed out.
authors.affiliation: State Key Laboratory of Materials Processing and Die Mould Technology, Huazhong University of Science and Technology (HUST), No. 1037, Luoyu Road, Wuhan 430074, China. dwzeng@mail.hust.edu.cn and Hubei Collaborative Innovation Centre for Advanced Organic Chemical Materials, Wuhan 430062, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Materials Processing and Die Mould Technology, Huazhong University of Science and Technology (HUST), No. 1037, Luoyu Road, Wuhan 430074, China. dwzeng@mail.hust.edu.cn.
authors.forename: Ziyu
authors.initials: Z
authors.lastname: Qin
authors.affiliation: State Key Laboratory of Materials Processing and Die Mould Technology, Huazhong University of Science and Technology (HUST), No. 1037, Luoyu Road, Wuhan 430074, China. dwzeng@mail.hust.edu.cn and Hubei Collaborative Innovation Centre for Advanced Organic Chemical Materials, Wuhan 430062, China.
authors.forename: Dawen
authors.identifier: http://orcid.org/0000-0002-0454-6751
authors.initials: D
authors.lastname: Zeng
authors.affiliation: State Key Laboratory of Materials Processing and Die Mould Technology, Huazhong University of Science and Technology (HUST), No. 1037, Luoyu Road, Wuhan 430074, China. dwzeng@mail.hust.edu.cn.
authors.forename: Changsheng
authors.initials: C
authors.lastname: Xie