One-step thermal compensation decomposition synthesis of ZnWO4/WO3 composite with synergy of multiple structural effects for efficient trace H2S detection

• Published in: Sensors and actuators. B, Chemical Chemical, 2023-04, Vol.381, p.133388, Article 133388
• Main Authors: Hu, Pengfei, Chen, Jingtao, Ma, Qianru, Yin, Jiaqi, Zhou, Dong, Kou, Chunhe, Xu, Jing, Xu, Jiaqiang
• Format: Article
• Language: English
• Subjects: Gas sensors; In-situ growth; Thermal compensation; Trace H2S; ZnWO4/WO3 heterostructures
• ISSN: 0925-4005; 1873-3077
• DOI: 10.1016/j.snb.2023.133388

WO3-based composites containing ZnWO4/WO3 heterojunction were prepared by a one-step thermal compensation decomposition process. The thermal compensation agent plays an important role in improving thermal decomposition efficiency, particle size and particle dispersion regulation. This process is very simple to mass produce spherical WO3 nanoparticles with excellent short-range electron transport ability, while abandons the cumbersome synthesis of eye-catching fancy structures. Core-shell-shaped and mulberry-type configuration of nanoparticles are the mainstream morphology of this process. They are endowed with excellent gas sensitivity to H2S, accompanied with strong selectivity and cycle stability, especially the low detection limit as low as 0.0783 ppm. A convincing gas-sensing mechanism with synergy of multiple structural effects have been proposed, including the temperature dependence of vacancy oxygen restricting the optimal working temperature of gas sensors, spherical nanostructures providing short distance of electron migration, and heterojunctions promoting electron migration. ZnWO4/WO3-heterojunction-based nanostructures prepared in situ by thermal decomposition will have broad prospects in the detection of trace H2S. [Display omitted] •One-step heat-compensation decomposition was set to fabricate WO3-based composite.•Controlling the synthesis temperature, size, dispersion and morphology by additives.•The heat-compensation decomposition realizes energy-saving and efficient output.•ZnWO4/WO3 heterostructures hold excellent gas sensitivity for H2S.