Flexible Full-Surface Conformal Encapsulation for Each Fiber in Graphene Glass Fiber Fabric against Thermal Oxidation.

Encapsulation for carbon-based electronic devices against oxidation can enhance their long-term working stability. Graphene glass fiber fabric (GGFF), as an advanced flexible electrothermal material, also struggles with graphene oxidation. The flexible, full-surface, conformal encapsulation for each fiber in the large-area fabric puts forward high requirements for encapsulating materials and techniques. Herein, the nanometer-thick h -BN layer was in situ grown on cambered surfaces of each fiber in GGFF with the chemical vapor deposition method. Stable heating duration (500 °C) of h -BN-encapsulated GGFF ( h -BN/GGFF) was increased by 1 order of magnitude without compromising the electrothermal performances and flexibility. Theoretical simulations revealed that the enhanced oxidation resistance of h -BN/GGFF was attributed to the decreased interaction and adsorption life of oxygen. The proposed flexible, full-surface, conformal encapsulation technique targeting the fiber-shaped graphene electrothermal device is scalable and can be extended to the other carbon materials, even devices with intricate shapes, which will promote the development of flexible electronics.