Piezoelectric/triboelectric nanogenerator based on PVDF/SBS flexible composite fiber film

Piezoelectric nanogenerators and friction nanogenerators can convert irregular mechanical energy into electrical energy which have the potential to provide independent and continuous power supply for low-power wearable electronic devices. Combining two kinds nanogenerators can integrate the advantages of their electrical output characteristics and improve the performance of nanogenerators. In this paper, polyvinyl fluoride (PVDF) and styrene butadiene styrene block copolymer (SBS) were selected as positive and negative friction materials, respectively. The PVDF/SBS composite fiber films were prepared by electrospinning and were employed to build a piezoelectric/triboelectric nanogenerator. The results show that when the amount of PVDF is 20wt%, the maximum open circuit voltage and short circuit current of the PVDF/SBS piezoelectric/triboelectric nanogenerator can reach 108 V and 0.34 μA, which are 5 and 6 times that of neat SBS sample, respectively. When the devices were fixed on the palm and sole of the shoe, output voltage signal with different amplitude can be obtained by collecting the mechanical energy of human motion, including clapping, walking and running. 64 commercial blue LED beads were lit up when the device were beaten by palm. The device can also detect the instantaneous pressure and the maximum sensitivity can reach 3.685 V·N⁻¹. The experimental results show that PVDF/SBS piezoelectric/triboelectric nanogenerator exhibits a good application prospect in the fields of sensor monitoring and self-energy supply of electronic devices.