Preparation and performance of electroless silver composite films based on micro-/nano-cellulose

High absorption and low reflection electromagnetic interference (EMI) shielding films were urgently required to solve increasingly serious radiation pollution. Micro-/Nano-cellulose (MNC) electroless silver film was prepared to obtain ideal electromagnetic shielding performance. The change of electromagnetic shielding efficiency and the performance of the optimal conditions in the process of electroless Ag were analyzed from the standpoint of different electroless Ag concentration to obtain films with excellent electromagnetic shielding. The results showed that Ag particles formed a dense and uniform coating with gradually increasing AgNO₃ concentration from 0.05 to 0.125 mol/L. The surface conductivity of the film increased from 1 to 20 S/cm and the surface roughness was 4 μm. The diameter of Ag microcrystalline particles was 18 nm. The contact angle of films was 99°. Here, the electromagnetic shielding efficiency was up to 41 dB in the frequency range from 0.03 to 3000 MHz, indicating that the electromagnetic wave absorption rate of composite films has reached 99.9%, which demonstrated that the EMI shielding mechanism was attributed to the high absorption.