Triboelectric Nanogenerators for Marine Applications: Recent Advances in Energy Harvesting, Monitoring, and Self-Powered Equipment

Progress in advanced electronics has initiated the investigation of new ways to develop and apply self-powered smart devices. The concern for meteoric exhausting non-renewable energy sources has spurred such endeavors. Even so, using external power sources like batteries is problematic due to limited capacity, maintenance inconvenience, replacement, and environmental hazards. Triboelectric nanogenerators (TENGs) capable of converting various forms of mechanical energies into electrical output are gaining popularity. The marine and coastal areas are abundant sources of salvable mechanical energy. TENGs can convert lower-frequency, ununiform, multidirectional energies into usable electricity. This can solve the device-powering problem and can generate diverse signals to act as monitoring or sensing platforms themselves. In this review, three main TENG-based/TENG-driven application themes are addressed, i.e., energy harvesting, marine environment monitoring, and self-powered equipment for marine-related activities. It attempts to emphasize that various design features of TENGs can influence output performance; TENGs can power devices and monitor ocean parameters; TENGs-integrated modern IoT networking systems can transmit real-time data. Overall, this review encompasses the fundamental working mechanisms, structure designs, and practical implementation scenarios of recently developed devices in diverse marine applications. Finally, the existing challenges and potential future directions for TENG-based marine self-powered electronic systems are discussed.