Finite Element Modeling of MXene/PVDF-Based High-Performance Triboelectric Nanogenerators for Self-Powered Wearable Electronics

Triboelectric nanogenerator (TENG)-based wearable devices have received a lot of attention in recent years; however, the power generation of these devices is still not up to the mark. Incorporation of functionalized materials into the TENG structure can improve the power generation of triboelectric nanogenerators, which can significantly revolutionize the TENG-based self-powered wearable electronics industry. This work comprehensively analyzes 2D MXene (Ti3C2Tx)-functionalized poly(vinylidene fluoride) (PVDF)-based TENGs as high-power wearable devices using electrostatics physics-based finite element modeling. Two distinct modes of TENGs are modeled: single electrode (SE-TENG) and contact separation (CS-TENG). The SE-TENG structure is studied to harvest energy from human skin directly. Hence, skin and MXene/PVDF are paired in this structure to develop devices like skin-attached sensors. The CS-TENG structure is developed with nylon and MXene/PVDF tribo-pairs for potential applications as fibers in textiles. The incorporation of MXene in PVDF leads to a significant improvement in dielectric constant and surface charge density, thereby boosting overall device performance. However, when the MXene percentage exceeds 10%, the dielectric properties of MXene/PVDF decrease due to percolation, lowering the device output. With 10% MXene incorporated PVDF, the SE-TENG structure demonstrates the highest open-circuit voltage, transferred charge, and power generation of 405 V, 221 nC, and 1.3 mW, respectively. The CS-TENG structure also shows excellent results with voltage, charge, and power profiles of 3365 V, 341 nC, and 13.07 mW, respectively. Because of these high-power outputs, as well as the flexibility and lightweight nature of MXene/PVDF, it holds tremendous possibility as a material choice for TENG-based wearable devices in the future.