PDMS Surface-Area Optimization for High-Performance Oscillatory Motion Harvesting Pendulum-Type Triboelectric Nanogenerators for Energy Harvesting and Sensor Applications

Triboelectric nanogenerators (TENGs) are generating a lot of attention because of their capacity to extract mechanical energy from everyday life. A pendulum motion is one of the ambient physical motions often seen in everyday human activities. Unfortunately, the pendulum motion is not efficiently harvested due to device fabrication complications. In this report, we developed a simple pendulum-type TENG (P-TENG) that could efficiently harvest the oscillating motion with the lateral-sliding and contact-separation TENG working mechanism. Polydimethylsiloxane (PDMS) film and paper were used as negative and positive triboelectric materials, respectively. A reverse-imprinting method was used to create micropatterned PDMS (MP-PDMS) to increase the surface area and achieve high electrical performance. The work function and tensile strength were also evaluated for the fabricated MP-PDMS films. Initially, the electrical response and output performance of MP-PDMS were optimized by employing it in a simple traditional TENG structure. Afterward, the optimized MP-PDMS films were employed in the P-TENG structure. The TENG was used to capture mechanical energy and store it in a capacitor so that a small-scale electronic device might be powered. Furthermore, the P-TENG was used to capture mechanical energy from the pendulum motion, and its real-time application as an angle detector was demonstrated. This work demonstrates the effective harvesting of oscillating motion available in everyday human life and powering of portable electronics as well as an angle sensor.