Progress and recent advances in self-powered gas sensing based on triboelectric and piezoelectric nanogenerators

Gas sensors play a crucial role in day-to-day life due to their application in leakage detection, environmental monitoring, and healthcare applications. Self-powered gas sensors (SPGS) are rapidly emerging, harnessing ambient energy sources. Various energy harvesting sources, such as photovoltaics, PENG, triboelectric nanogenerators, and thermoelectric generators, were used to design and fabricate SPGS. These devices provide uninterrupted power to gas sensors and replace bulkier, environmentally harmful batteries. In addition, these batteries require periodic replacement and frequent charging for their continuous operation. Although the field of SPGS was emerging, moving towards commercialization needed significant progress in device design, materials, and power management. This review focuses on innovative device designs, novel materials, and types of gas sensors reported so far, and the details are systematically categorized. Also, this review envisions and discusses the future trends in the SPGS and the potential path to commercialization.