Hybrid nanogenerator driven self-powered SO2F2 sensing system based on TiO2/Ni/C composites at room temperature

The application of conventional sensors is limited due to energy supply issues and environmental problems, and current triboelectric nanogenerator (TENG) based self-powered sensing systems is hard to meet the specific requirement. In this paper, TiO2/Ni/C composites were prepared using MOF-derived Ni/C materials for SO2F2 detection at room temperature. The excellent pore structure and high electrical conductivity of Ni/C material greatly improve the sensitivity properties of TiO2. The TiO2/Ni/C composites-based SO2F2 sensor exhibits a wide detection range of 5–200 ppm concentration and a fast response/recovery time of 26 s/9 s, while its response value for 200 ppm SO2F2 is 18.34 times higher than that of the pure TiO2-based sensor. Furthermore, by modifying the PVDF film with TiO2, the permittivity of PVDF is greatly improved, and the surface potential is 2.6 times higher than that of pure PVDF film. Eventually, a dual-layer hybrid TENG based on TiO2/PVDF composite film was constructed. Its upper TENG powers the TiO2/Ni/C composite sensor, and the lower hybrid TENG drives the thermohygrometer to realize a self-powered temperature and humidity-corrected SO2F2 sensing system, which can accurately implement SO2F2 gas concentration alarms at 10 ppm, 50 ppm, and 100 ppm at different humidity levels. This work broadens the application of TENG in the field of self-powered gas sensing while providing a new idea to achieve the trace detection of SO2F2 at room temperature.