Synergy of Active Sites and Charge Transfer in Branched WO3/W18O49 Heterostructures for Enhanced NO2 Sensing

• Published in: ACS sensors Vol. 9; no. 3; pp. 1391 - 1400
• Main Authors: Zheng, Qiuyue, Wang, Tingting, Zhang, Guanyi, Zhang, Xianfa, Huang, Chaobo, Cheng, Xiaoli, Huo, Lihua, Cui, Xinlei, Xu, Yingming
• Format: Journal Article
• Language: English
• Published: American Chemical Society 22.03.2024
• Subjects: practical application; active sites; NO2 sensing; WO3/W18O49 heterostructures; charge transfer
• ISSN: 2379-3694; 2379-3694
• DOI: 10.1021/acssensors.3c02443

Achieving reliable detection of trace levels of NO2 gas is essential for environmental monitoring and protection of human health protection. Herein, a thin-film gas sensor based on branched WO3/W18O49 heterostructures was fabricated. The optimized WO3/W18O49 sensor exhibited outstanding NO2 sensing properties with an ultrahigh response value (1038) and low detection limit (10 ppb) at 50 °C. Such excellent sensing performance could be ascribed to the synergistic effect of accelerated charge transfer and increased active sites, which is confirmed by electrochemical impedance spectroscopy and temperature-programmed desorption characterization. The sensor exhibited an excellent detection ability to NO2 under different air quality conditions. This work provides an effective strategy for constructing WO3/W18O49 heterostructures for developing NO2 gas sensors with an excellent sensing performance.