Piezo/Triboelectric Effect Driven Self-Powered Gas Sensor for Environmental Sensor Networks

With the growing concern about the safety of the spaces where people work and live, the development of fast and accurate real-time safety monitoring systems such as gas sensors to detect harmful gas such as H₂S, NH_3, and NO_x is essential. For effective monitoring, a wireless sensor system that can be used anytime, anywhere is required, but there is still a limit to the power supply to operate it. Self-powered gas sensors with piezoelectric/triboelectric nanogenerators (PENGs/TENGs) are receiving considerable attention because they can implement portable gas sensors that do not require an additional power source. Herein, the latest developments in piezoelectric/triboelectric effect based self-powered gas sensors are summarized and discussed. The first part of this review discusses the fundamental aspects and strategies of the self-powered active gas sensor based on the piezoelectric and triboelectric effects. The second part focuses on the self-powered gas sensors that operate on energy generated by piezoelectric and TENGs.