γ-ray induced microstructure modulation for enhanced output performance of polyimide-based piezoelectric composites

Abstract

High-performance piezoelectric composites (PCs) with on-demand properties hold significant potential for diverse soft energy applications, owing to their enhanced efficiency and reliability compared to single-type materials. However, traditional approaches to improving the piezo-performance of PCs face limitations regarding universality, device stability, and integration with commercial manufacturing processes. Here, we address these challenges by employing gamma-ray-material interaction, a simple and scalable method to modify the physical and electrical properties of composites. Using density functional theory and molecular dynamics simulations on hybrid systems comprising modified (K,Na)NbO3 fillers and a polyimide matrix, we find that gamma-ray induced chain scission enhances elastic constant and piezoelectric voltage constant, simultaneously. These two effects collectively improve stress transfer efficiency and significantly boost the piezoelectricity of PC. Experimental results show that the gamma-ray irradiated composites exhibit a 240 % increase in output voltage compared to a control device. By offering an easily implementable and robust approach for high-performance PCs, our findings open new avenues for developing piezoelectric devices with superior energy harvesting efficiency and broad industrial applicability.