Low‐Temperature In Situ Constructed Ag‐Graphene Films for Wearable Electronics with Broadband EMI Shielding, Environmental Tolerance, and Efficient Thermal Management

With the rapid development of wearable flexible electronics, flexible materials integrating high conductivity, superior electromagnetic interference (EMI) shielding performance, and structural stability have become an imperative trend. In this study, a high-performance flexible silver-graphene composite film is successfully fabricated using a metal-organic decomposition (MOD) ink-graphene hybrid strategy. This approach utilizes MOD ink to selectively grow silver nanoparticles at graphene defect sites, constructing an anchored dense conductive network. The as-prepared Ag-G film (≈40 µm) exhibits exceptional comprehensive properties: an average electrical conductivity of 1.9 × 10⁵ S·m^-1 and an EMI shielding effectiveness (SE) of 69.8 dB over the 8.2-18 GHz frequency range, along with outstanding structural stability. Remarkably, after harsh treatments (strong acid/alkali immersion, ultrasonic agitation, bending cycles, and water bath immersion), the film retains >96% of its initial EMI SE. Meanwhile, the in-plane and out-plane thermal conductivity reach of 4.92 and 0.68 W (m·K)^-1. Furthermore, leveraging the low viscosity of MOD ink, large-area film fabrication is achieved via spray coating, offering a lightweight and highly reliable solution for electromagnetic protection in flexible wearable electronics.