Influence of dispersed phase morphology on electrical and fatigue properties of BaTiO3/PDMS nanogenerator

Abstract

A flexible piezoelectric nanogenerator (FPENG) was fabricated by incorporating barium titanate (BT) fibers and BT powders into polydimethylsiloxane (PDMS) matrix phase, also with an interdigital electrodes (IDEs). The electrospinning method was used to prepare BT fibers. Phase structure was carried out by the x-ray diffraction (XRD) technique. By using the Rietveld refinement method, a tetragonal structure of BT fiber could be confirmed. The scanning electron microscopy results showed a non-smooth surface of BT fibers, indicating the polymeric and organic precursors have been removed. The fabricated FPENG with 50% ratio of BT fibers was capable to generate an open-circuit voltage of ≈ 12 V and a short-circuit current of ≈ 1 μA. The effect of dispersed phases inside FPENG becomes the role to improve the output performance. This FPENG device can operate up to 5k times before degeneration. By continuously pressing up to 40k times, the output voltage tended to decrease reaching to a null value. The mechanical fatigue effect has been found that it related to the damage produced at the interface between IDEs and PDMS during pressing. The present results can be guided to further design the material and the device structure to obtain high-performance and stability of the FPENG devices.