Abstract
Vibration in mechanical equipment can serve as a sustainable energy source to power sensors and devices if it can be effectively collected. In this work, a honeycomb structure inspired triboelectric nanogenerator (HSI-TENG) consisting of two copper electrode layers with sponge bases and one honeycomb frame filled with polytetrafluoroethylene (PTFE) balls is proposed to harvest vibration energy. The application of a compact honeycomb structure increases the maximum power density of HSI-TENG by 43.2% compared to the square grid structure and provides superior advantages in large-scale manufacturing. More importantly, the nonspring-assisted HSI-TENG can generate electricity once the PTFE balls obtain sufficient kinetic energy to separate from the bottom electrode layer regardless of the vibration frequency and direction. This is fundamentally different from the spring-assisted harvesters that can only work around their natural frequencies. The vibration model and working criteria of the HSI-TENG are established. Furthermore, the HSI-TENG is successfully used to serve as a self-powered sensor to monitor engine conditions by analyzing the electrical output of the HSI-TENG installed on a diesel engine. Therefore, the nonspring-assisted HSI-TENG provides a novel strategy for highly effective vibration energy harvesting and self-powered machinery monitoring.