Self-Powered Water Quality Monitoring Using AlGaN/GaN Hemt Powered By Rotational Teng

Water pollution poses significant threats to ecosystems and human health leading to long-term environmental damage even at trace concentrations. Traditional water monitoring systems often require external power sources, limiting their applicability for continuous, remote and sustainable operations. High-electron-mobility transistors (HEMTs) are widely recognized for their superior electron mobility, exceptional sensitivity and linear response making them ideal candidates for high-precision sensing applications. In this study, we present a novel self-powered environmental monitoring system that combines AlGaN/GaN HEMT based sensor with a rotational triboelectric nanogenerator (R-TENG) for detecting multiple water pollutants including pH, heavy metal ions (such as Cr 6+ , As 3+ , Pb 2+ ), pesticides and microplastics. The system is encapsulated with acrylic layers and utilizes magnetic coupling to operate effectively under aquatic conditions. R-TENG generates a stable output of 75 V and 7 μA at a rotational speed of 100 rpm with a peak power of 76.64 μW at a switching frequency of 60 Hz. This energy powers HEMT sensor which exhibits high pH sensitivity (-13.93 mA/pH) with excellent linearity. Furthermore, the sensor demonstrates remarkable capability in detecting pollutants at trace levels distinguishing concentrations as low as nanomolar ranges for heavy metals and pesticides. Comparative analyses of pollutant responses revealed distinct trends based on ionic size and charge carrier dynamics showcasing the system’s ability to differentiate between contaminants. The encapsulated design ensures device stability with SEM analysis confirming no significant damage to the sensing surface after extended operation. By leveraging water wave energy, this self-powered system provides a sustainable solution for long-term with continuous water quality monitoring in remote or harsh aquatic environments. Its innovative integration of R-TENG with HEMT sensors offers a versatile and efficient platform for comprehensive environmental analysis.