The importance of interface interactions in flexible sensing materials: classification, effect, and application

Flexible sensors have become the hotspot of wearable electronic devices today due to the advantages of adaptability and wearing comfort. This paper reviews the performance parameters of flexible strain sensing, categorizes the interfacial interactions based on different effects, and discusses the applications of flexible strain sensors based on interfacial interactions in biomedical applications , sports performance monitoring, and human–computer interaction technologies. • Summarizes recent advances in interfacial interaction effects for flexible strain sensing. • Flexible sensing via interface interactions boosts biomedical, sports, and human-computer applications. • The challenges and future research directions of flexible sensing based on interfacial interactions are presented. Flexible sensors have become a hotspot in wearable electronics today. They are widely used in artificial intelligence, electronic skins, and human–machine interfacial interactions due to the advantages of adaptability and comfort. It is necessary to consider not only the characteristics of the sensing material but also the complex interfacial interactions. This review focuses on the fundamental characteristics of various interfacial interactions, discusses their effects on sensing performance, and summarizes the relevant applications. Through in-depth analysis of the interfacial interaction, we can gain a deep insight into the design strategy of flexible sensors and methods to improve their sensing performance. We hope this review can provide valuable perspectives on the design of higher performance flexible strain sensors.