Wireless self-powered sensor networks driven by triboelectric nanogenerator for in-situ real time survey of environmental monitoring

Reusing waste materials to create energy harvester will not just reduce the environmental pollution, but also generate renewable electricity by scavenging environmental energy to power wireless electronic devices, which will make our life more environmental friendly. In this study, we first turn waste milk carton into fully packaged arc-shaped triboelectric nanogenerator (AS-TENG) which can scavenge both wind and water flow energy for long-term wireless environmental monitoring. In general, the milk carton is laminated (from inside out) with a layer of polyethylene (PE), a layer of aluminum (Al) foil and a pulp layer. Such laminated material is suitable as the electrical unit of the AS-TENG. The arc-shaped design of AS-TENG is implemented to disrupt the flow, leading to vortex induced vibration, and thus contact electrification of the AS-TENG results in power generation. By optimizing the structural parameters systematically, the AS-TENG achieves an instantaneous peak voltage of 600 V, and a current of 40 mu A. Moreover, a self-powered wireless environmental monitoring system using AS-TENG as power supply is developed for in-situ real time water quality (pH value) monitoring and landslide early warning in natural environment. This study provides solid progress toward the practical applications of TENGs in environmental monitoring.