Natural biomass-based multifunctional conductive composite films integrating personal thermal management, electromagnetic interference shielding, and physiological signal sensing

Abstract

With the rapid advancement in 5G communications, conductive composites integrating personal thermal management (PTM) and electromagnetic interference (EMI) shielding capabilities have garnered extensive attention in the fields of electronic devices and sensors. However, conductive composites still suffer from high preparation costs, poor biocompatibility, inadequate mechanical properties, and limited functionality with a narrow application scope. Herein, a natural biomass-based multifunctional conductive composite film (DSAC) was proposed, which synergistically integrates PTM, EMI shielding, and physiological signal sensing capabilities. Specifically, DSAC was fabricated by incorporating carbon nanotubes (CNTs) and silver nanoparticles (AgNPs) into an oxidized corn starch/silk fibroin/poly(vinyl alcohol) (DCS/SF/PVA) matrix via supramolecular assembly. This DSAC demonstrated remarkable toughness; stretchability; antimicrobial activity; self-adhesive, antioxidant, and UV-shielding properties; and good biocompatibility alongside superior EMI shielding effectiveness and PTM capability. Notably, the prepared film could be heated from room temperature to 120 °C within 15 s and rapidly cooled back to room temperature immediately after the light source was removed. Moreover, the DSAC sensor displayed advanced electrical conductivity and high sensitivity toward temperature, strain, bioelectric signals, subtle facial microexpressions, and various human movements. This natural conductive composite design provides an innovative strategy for preparing smart wearable devices integrating PTM, EMI shielding, and physiological signal sensing.