Energy harvesting and self-powered microphone application on multifunctional inorganic-organic hybrid nanogenerator

Highlights: • A flexible multifunctional piezoelectric nanogenerator is demonstrated. • It possesses resonance frequency at 86 ± 3 Hz and an acoustic sensitivity of ∼3 V Pa⁻¹. • It is capable of acting as a self-powered microphone for sound recording. • A very high wind energy conversion efficiency of ∼58% is achieved. • It is capable of detecting human exhalation. -- Abstract: Piezoelectric nanogenerators are forthcoming alternative choices for scavenging different types of wasted mechanical energies. An inorganic-organic hybrid piezoelectric nanogenerator (HPNG) has been realized by incorporating zinc sulphide nanorods (ZnS-NRs) into electrospun poly(vinylidene fluoride) (PVDF) nanofibers for self-powered multifunctional sensing. As an acoustic energy harvester, the HPNG possesses a resonance frequency of 86 ± 3 Hz and an acoustic sensitivity of ∼3 V Pa⁻¹. It can distinguish sound waves from low to mid frequency region that makes it suitable for noise detection. In addition, HPNG demonstrates the very high wind energy conversion efficiency of ∼58% that make it capable of detecting human exhalation. Apart from its noise detection and power generation capabilities, HPNG is possible to use as a self-powered microphone. This electromechanical coupling, integrated with their flexibility, makes it usable as a flexible electro-acoustic sensor for security purpose as well. These results establish the potential of hybrid piezoelectric structure, with their multi functionalities for several promising applications such as noise detection, wind energy harvesting, security monitoring and most promisingly to develop the self-powered system.