Enhancing charge transfer via dual active sites in SnO₂@ZnSn(OH)₆ heterojunctions for high-performance MEMS humidity sensors
Hu W. Zhang M. Yao X. Ibraimov M. Qiu S. Du J. Tuokedaerhan K. Qu F.
20 March 2026Elsevier Ltd
Journal of Alloys and Compounds
2026#1059
Efficient charge transfer is crucial for enhancing the performance of semiconductor-based humidity sensors. In this study, we designed and fabricated a high-performance humidity sensor based on a SnO₂@ZnSn(OH)₆ (ZHS) heterojunction. First-principles calculations revealed that the SnO₂@ZHS heterojunction exhibits strong interfacial interactions that induce lattice mismatch and charge redistribution, which weaken Sn–O bonds and facilitate the formation of oxygen vacancies. These vacancies serve as shallow donors, partially reducing Sn⁴⁺ to Sn³ ⁺ and forming Sn³ ⁺–OV defect centers. The synergistic effect of oxygen vacancies and Sn³ ⁺ ions generates local electric fields, stabilizes water adsorption (with adsorption energy of −1.492 eV compared to −0.521 eV for pure ZHS), and promotes efficient interfacial charge transfer. Experimentally, the SnO₂@ZHS composite demonstrated excellent humidity-sensing performance at room temperature, with high sensitivity (10 MΩ → 3 kΩ), a wide detection range (11–95% RH), rapid response/recovery times (3/10 s), and outstanding long-term stability. Furthermore, a Micro Electromechanical System (MEMS) electrode substrate was designed and fabricated to demonstrate the feasibility of device miniaturization and system integration. This strategy provides new design approaches and application prospects for industrial humidity monitoring and human respiration monitoring.
Charge transfer efficiency , Humidity sensors , MEMS electrode substrate , SnO₂@ZnSn(OH)₆ heterojunction
Text of the article Перейти на текст статьи
Xinjiang Key Laboratory of Solid-State Physics and Devices, Xinjiang, Urumqi, 830046, China
School of Physics Science and Technology, Xinjiang University, Xinjiang, Urumqi, 830046, China
School of Materials Science and Engineering, Xinjiang University, Xinjiang, Urumqi, 830046, China
Educational Laboratory of Semiconductor Device Engineering, Faculty of Physics and Technology, Al Farabi Kazakh National University, Almaty, 050040, Kazakhstan
School of Microelectronics, Northwestern Polytechnical University, Xian, 710072, China
Xinjiang Key Laboratory of Solid-State Physics and Devices
School of Physics Science and Technology
School of Materials Science and Engineering
Educational Laboratory of Semiconductor Device Engineering
School of Microelectronics
10 лет помогаем публиковать статьи Международный издатель
Книга Публикация научной статьи Волощук 2026 Book Publication of a scientific article 2026