Electrosprayed boron nitride nanosheet aggregates for enhanced acoustic energy harvesting with poly(vinylidene fluoride) nanofiber membranes

While often regarded as an annoyance, noise conceals a surprisingly abundant source of untapped energy that can be efficiently harvested to power a variety of micro-devices. However, achieving high electric outputs from acoustic energy harvesters remains a formidable challenge. In this study, we employ a one-step approach that integrates electrospining and electrospraying techniques to fabricate a single-layer composite membrane, comprising a poly(vinylidene fluoride) (PVDF) nanofiber network with uniformly dispersed boron nitride nanosheet aggregates (BNNS-A) for sound energy harvesting. Our 3 x 4 cm2 +PVDF/-BN device generates peak voltage and current outputs of 174.2 V and 19.2 mu A, respectively, when exposed to 115 dB, 230 Hz sound. Remarkably, this device exhibits the highest voltage output among other similar PVDF-based acoustoelectric devices operating under comparable sound conditions. Furthermore, the incorporation of BNNS-A enhances maximum peak power output by 30-fold compared to pure PVDF nanofiber devices. This study provides a profound understanding of endogenous triboelectricity mechanism in nanocomposites and presents a promising approach for producing high-performance nanofiber acoustoelectric devices.