High-Performance Triboelectric Nanogenerators Based on Foaming Agent-Modified Porous PDMS Films with Multiple Pore Sizes

Triboelectric nanogenerator (TENG), which is prepared from porous poly(dimethylsiloxane) (PDMS), has garnered considerable interest as a small, lightweight device capable of harvesting various forms of mechanical energy. However, the long fabrication period, hazardous reagents, complicated processes, and high costs limit its application in the wearable field. In this study, the porous PDMS film TENG (F-TENG) was prepared by modifying PDMS with three foaming agents. The whole process has the advantages of having a short production cycle and being simple and safe. The specific surface area of porous PDMS films was significantly improved compared to pure PDMS films. The F-TENG prepared from porous PDMS with the smallest pore size exhibits the largest specific surface area and the best output performance. The effect of the weight percentage of the doped foaming agent on the output performance was investigated. The results indicated that the optimal performance was obtained when 8 wt % of azodicarbonamide was doped. At this doping level, the F-TENG achieved an open-circuit voltage of 100.38 V and a short-circuit current of 3.99 μA, which were 3.71 times and 3.12 times higher than those of PDMS-TENG. Furthermore, the device can collect mechanical energy from the movements of multiple parts of the body and convert it into electrical signals. When integrated with rectifier circuits and capacitors, the F-TENG can constitute a self-powered system to power small appliances. The electronic system has great application potential in the fields of wearable devices, self-powered sensing, and power supply of microelectronic devices.