Piezoionic effect in gels: multifunctional applications from energy harvesting to intelligent sensing

Piezoionic gels, an emerging stimuli-responsive material composed of flexible polymer networks and mobile ionic species, exhibit efficient mechanoelectrical transduction capability, garnering significant research interest for applications in energy harvesting and intelligent sensing. In order to further investigate their operating mechanisms, optimize performance, and expand application scenarios, this review summarizes the recent advancements in piezoionic gels, focusing on the strategies employed to enhance their mechanoelectrical transduction capabilities and mechanical performance. We also explore their potential applications in energy harvesting and intelligent sensing. This review provides valuable insights and guidance for the development and application of high-performance piezoionic gels by systematically analyzing the physical mechanisms of the piezoionic effect, outlining the performance enhancement strategies under various modes, and further discusses current challenges and opportunities.