“…Modern living environments host a wide range of ambient natural and artificial energy sources, such as solar, wind, wave, heat, vibrations, electromagnetic waves, and human activities . Over the past decade, technologies to harness these renewable energy sources have been intensively investigated, including wireless energy harvesting systems, such as triboelectric, − magnetoelectric (ME), − thermoelectric, − piezoelectric, − photovoltaic (PV), , radio frequency (RF), , and magnetic field energy harvesting. − These efforts have resulted in rapid advances in the performance of energy harvesting systems. For example, triboelectric nanogenerators (TENGs) have shown that the instantaneous output power density has initially increased from a few micrometers cm –2 to several tens of mW cm –2 .…”