Hybrid organic-inorganic functional nanocomposites: From basis to applications in stretchable sensing and energy devices

Abstract

Hybrid organic-inorganic functional nanocomposites are crucial in advancing electronics, biomedicine, and environmental science. These multifunctional and multiphase systems combine flexibility and stretchability with a broad spectrum of functional properties. This review delves into the fundamental (di)electric, thermal, and mechanical properties of these materials; the recent developments in their design and processing; and their application in strain, pressure, thermal sensing, energy harvesting, and energy storage. First, emphasis is placed on the role of nanofiller dimensions, spatial distribution, and interface interactions in enhancing material functionalities through meticulous control of the filler loading described by the universal percolation theory. Then, essential stages in nanocomposite fabrication, such as dispersion and deposition, are explored, as those significantly affect final properties. Finally, the review examines reported applications in stretchable electronics, such as mechanical sensors (piezo- and thermoresistive), energy harvesters (photovoltaic, piezoelectric, and thermoelectric), and energy storage devices (nanodielectric and electrochemical). Design strategies to balance functionality and stretchability are discussed, providing a roadmap for future research and development in this vibrant field.