Title: PVBVA/Ti3C2Tx MXene Composites for Additively Manufactured and Electrospun Triboelectric and Multifunctional Wearable Electronics Program: Materials Science and Engineering PhD Committee Chair: Dave Estrada Committee: Dave Estrada, Zhangxian Deng, Brian Jaques, Jessica E. Koehne Abstract: Triboelectric nanogenerators (TENGs) offer a promising route for harvesting mechanical energy for wearable electronics, healthcare monitoring, and human–machine interfaces, but current systems often depend on fluorinated polymers and complex fabrication. We address these limitations using a sustainable poly(vinyl butyral co vinyl alcohol co vinyl acetate) (PVBVA)/Ti3C2Tx MXene composite processed through direct ink writing (DIW) and electrospinning. In the DIW approach, printed PVBVA/MXene films on flexible substrates show optimal performance at 5.5 mg/mL MXene, achieving a power density of 760 mW·m?² with 129% and 250% increases in open circuit voltage and short circuit current. A fully printed, aluminum free device with silver electrodes demonstrates robust real time motion sensing (walking, running, bending, jumping). Extending this platform to electrospun fibers enables a multifunctional electronic tattoo (e tattoo) using a PVBVA/ Ti3C2Tx/PVBVA (PMxP) architecture. The device delivers 250 V, 2.9 µA, and 250 mW·m?², while also exhibiting capacitive behavior (14 pF at 10 kHz) and high quality ECG/EMG acquisition with excellent skin conformability. Across both strategies, Ti3C2Tx MXene enhances triboelectric output, dielectric response, and interfacial charge transport. Initial radiation stability studies of PVBVA under X ray exposure reveal changes in dielectric behavior, establishing a baseline for developing radiation resilient wearable substrates and health monitoring systems.
