▎ 摘　　要

In recent years, multifunctional materials have attracted widely attention due to its application in wearable electronic devices. However, it is a challenge how to balance multifunctional performance of materials. It is an issue to obtain film with the lightweight and mechanically flexible film with electromagnetic interface (EMI) shielding and Joule heating performance. Graphene nanosheets (GNs) have been investigated as EMI shielding materials due to its high electrical conductivity. Herein, Janus film of GNs and bacterial celluloses (BCs) is constructed via a vacuum-assisted filtration technique for achieving lightweight and mechanically flexible film with excellent EMI shielding performance and Joule heating performance. GNs/BCs Janus films exhibit excellent EMI shielding effectiveness of 70 dB in the X band and low voltage (3.0 V) driven Joule heating performance with the surface temperature of 111 degrees C. Hence, GNs/BCs Janus films have a broad application prospect in EMI shielding and personal thermal management fields.