(171v) Performance of Triboelectric Nanogeneration Using Flow through Porous Elastomers

Triboelectric nanogenerators (TENGs) have garnered significant interest as lightweight devices capable of converting low-frequency mechanical energy into electrical energy through triboelectrification and electrostatic induction. TENGs offer unparalleled advantages, including portability, lightweight design, flexibility, and responsiveness to low-frequency stimuli. In this study, we synthesize porous PDMS foams using a gas foaming technique, with sodium bicarbonate as the foaming agent. The PDMS pre-polymer is prepared by mixing Sylgard 184 and curing agent in a 10:1 mass ratio, followed by the addition of sodium bicarbonate and acetic acid in a 1:1 molar ratio. Pores in the PDMS foam are generated by CO₂ gas, resulting from the decomposition of sodium bicarbonate and its reaction with acetic acid. We achieve pores of different morphologies and sizes by systematically varying the foaming agent concentration from 0 to 5 wt%. Our hypothesis is that altering the pore morphology in the dielectric material affects the TENGs output performance. Therefore, precise control over the pore distribution and size is crucial for generating additional triboelectric charges and enhancing the performance of the triboelectric generator. The results indicated that the optimal performance was obtained at 1wt% foaming agent concentration with an open circuit voltage of 78.4 V and a short circuit current of 58 nA. This enhancement in electrical performance is attributed to the increased specific surface area and reduced effective thickness, leading to a higher capacitance value. This work experimentally assesses the performance of TENGs with a specific focus on pore size, analyzing and characterizing the pore structure and size distribution using micro-CT. The triboelectric performance of the fabricated samples is assessed using Cu/PDMS/Cu TENGs in vertical contact separation mode, evaluating the electrical output in response to periodic mechanical stimuli. In summary, this study presents a facile method for fabricating porous PDMS with enhanced triboelectric performance, durability, and flexibility.