npj Flexible Electronics (Sep 2021)
Flexible and transparent piezoelectric loudspeaker
Abstract
Abstract The simple structure of flexible piezoelectric polymers implies promise innumerous applications, such as transparent loudspeakers. In this study, we fabricated and characterized a prototype loudspeaker device. The loudspeaker was fabricated using a straightforward method of sandwiching a film of copolymer blend between a pair of flexible ITO substrates, which served as top and bottom electrodes. The dependence of acoustic properties of the devices was investigated in accordance with d 33 and piezoresponse force microscopy (PFM). In this study, we examine the sound pressure level (SPL) and sound intensity (SI) of devices featuring 0.5 ≤ α ≤ 0.9 blends, with an active area of 6.5 cm × 5 cm at 100 Vpp applied voltage. Here we report SPL of 96 dB and SI of 3.98 m Wm−2 for an α = 0.7 blend at 100 Vpp. Our results are helpful in developing flexible, transparent piezoelectric polymers and in the development of lightweight, transparent loudspeaker devices.