Flexible and stable piezoelectric nanogenerators based on monoclinic phase CsPbBr₃ perovskite nanocrystals

CsPbBr₃ perovskite has garnered significant attention in the field of optoelectronics due to its exceptional photoelectric properties. In this study, we report the fabrication of a piezoelectric nanogenerator (PNG) composed of a composite of monoclinic phase CsPbBr₃ nanocrystals and polydimethylsiloxane. This is the first instance of a PNG based on the monoclinic phase of CsPbBr₃. The PNG device has been optimized to operate at a frequency of 30 Hz and exhibits impressive output performance, generating a peak-to-peak output voltage of 50 V, an output current of 5.5 μA and a power density of 2.5 μW cm^-2 when subjected to an applied force of only 4.2 N over an effective area of 8 cm². The energy generated by this PNG can be efficiently collected using capacitors with a high energy conversion efficiency of 21.7%. Furthermore, the output voltage of the PNG remains at 98.5% of its initial value after 20 days, demonstrating exceptional stability. This study highlights the great potential of CsPbBr₃ perovskite materials for the simple and cost-effective fabrication of high-performance multifunctional piezoelectric energy harvesting devices.