Poly(vinylidene fluoride)/2D Layered Molybdenum-Based MXene Composite for Piezoelectric and Piezocatalytic Applications

Poly(vinylidene fluoride) (PVDF)-based piezoelectric nanogenerators (PENGs) have emerged as sustainable and lightweight materials for mechanical energy harvesting; however, their performance is often limited by insufficient electroactive phase content and weak interfacial polarization. In this work, we report the fabrication of flexible PVDF-based PENGs enhanced with 2D Mo-based MXene, used as controlled nucleating fillers. Comprehensive structural, thermal, dielectric, ferroelectric, and piezoelectric analyses of pristine PVDF and its nanocomposites revealed that the PVDF film containing 1 wt % MXene (P-1M) exhibits better functional performance suitable for nanogenerator applications. Piezoresponse force microscopy verified a high piezoelectric coefficient ( d 3 3 ≈ 27 pm/V) for the P-1M sample. The incorporation of MXene effectively induced electroactive phase formation in PVDF. The PVDF/MXene nanocomposite-based PENG demonstrated a power output of 15.86 μW under a periodic load of 25 N, generating a peak-to-peak voltage of 20 V and a current of 1.84 μA. The optimized device successfully powered light-emitting diodes, charged capacitors, and detected various human motions. Moreover, the as-fabricated film exhibited notable piezoelectric activity at different pressures with a sensitivity of 0.24 V/kPa in the low-pressure range and rapid response and recovery times of 6 and 27 ms, respectively, without the need for additional poling. Apart from this, the nanocomposite film demonstrated a piezocatalytic response by achieving 97% degradation of Rhodamine B dye through the production of reactive oxygen species under mechanical stress. Overall, these results show the multifunctional applications of PVDF@Mo-MXene nanocomposites in biomechanical energy harvesting, motion detection, powering of next-generation self-sustained electronic and sensing devices, and energy harvesting from waterfalls and water purification.