Highly Efficient and Controlled Thermomechanical Transfer of Electrospun PVDF Nanofiber on Flexible and Transparent PDMS Substrate

The growing interest in sensors and microdevices in different applications has led to the exploration of the most efficient and appropriate synthesis methods for flexible device development. In this direction, nanofibers have gained significant attention. However, in many cases, efficient and controlled transfer of nanofibers plays an important role in various device developments. In this study, thermomechanical i.e., temperature and pressure-induced transfer of poly(vinylidene fluoride) (PVDF) electrospun nanofibers on flexible poly(dimethylsiloxane) (PDMS) substrate has been explored. The average diameter of the transferred nanofibers is 169.78 nm. The d₃₃ of PVDF nanofibers was 25 pC/N and F(β) was found to be 80.84%. The synthesized nanofibers have effectively been transferred onto a flexible PDMS substrate with more than 92% retention of optical transparency. It is observed that the transfer of the fibers depends on the applied pressure and adhesion between the materials. Further, it was found that fully cured PDMS substrate heated at 120 °C showed better transfer efficiency (12.544%) with higher stability. The use of PVDF nanofibers along with the inherent flexibility and transparency of PDMS, renders the produced substrate highly promising for the development of low-cost, lightweight, and easily constructed flexible sensors. Moreover, the fabricated nanofibrous mat generated a maximum voltage of 2.78 V on continuous tapping.