Interface modulated 0-D piezoceramic nanoparticles/PDMS based piezoelectric composites for highly efficient energy harvesting application

Flexible piezoelectric nanogenerator (PENG) has been regarded as one of the promising solutions to harvesting mechanical energy, as a sustainable energy source for wearable devices , etc. Here, a universal strategy of carbon coating modulation is proposed to synthesis carbon coated 0-D piezoceramics nanoparticles (NPs). Owing to the good electric conductivity of carbon shell, the redistribution and accumulation of mobile charges in carbon layer gives rise to reinforcement of electric field, results in the much-enhanced piezoelectric effect. Polydimethylsiloxane (PDMS) composites with those 0-D piezoceramics NPs are used to fabricate PENGs. The peak power density of BT@C, PZT@C and KNN@C based PENGs reaches up to 45.4 μW/cm 2 , 59.8 μW/cm 2 and 9.9 μW/cm 2 , that are 20, 20.4 and 13.4 times larger than those of control PENGs incorporated with bare 0-D piezoceramic NPs, respectively. A theoretical model based on Lewis diffusion theory is constructed to reveal the mechanism of piezoelectric enhancement in the poling process. This research provides a new strategy for synthesis of high piezoelectric characteristic composites by embedding carbon coated 0-D piezoceramic NPs.