Microgroove-induced F-M growth mechanism of in-situ graphene deposition on carbon fibres for enhancing electrical conduction

The development of aerospace and aviation proposed urgent demands for lightweight, high-strength, and durable conductive materials. Carbon fibres (CFs) show great potential for application in present flexible conductive materials with high strength, lightweight and corrosion resistance. However, the intrinsic structural deficiencies of CFs limit the electrical conductivity and restrict their further applications. Herein, based on the proposal of the microgroove-induced F-M growth mechanism, a surface modification strategy through in-situ growth of graphene sheets is developed to successfully enhance the electrical conduction performance of CFs. With the induction of microgrooves, in-situ grown graphene can fill the surface gaps on the carbon fibres at the atomic level, offering pathways for rapid charge transport, and thereby enhancing the electrical conductivity of carbon fibres. Assisted by DFT calculation and experimental verification, the microgroove-governed growth pathway and the temperature/time dependency of graphene (CF@G) are verified. The electrical conductivity of CFs is markedly enhanced while retaining the good mechanical performance of CFs. The sheet resistance of the prepared CF@G clothes is reduced by 65.4% than the original CFs clothes, while the conductivity remains constant after 200 cycles of folding. Notably, the CF@G reinforced polymer (CF@G-CFRP) composite exhibits 101.5% enhancement in tensile strength compared to the widely used copper sheet-based conductive composites in industry. Due to the graphene sheets in-situ growth by microgroove-induced F-M mechanism, the CF@G composites exhibit a 106.9% increase in the effective electrical conductivity after graphitisation. This study presents a novel strategy for the design and optimisation of high-performance conductive materials, thereby facilitating the rapid advancement of lightweight requirements in the aerospace sector.