Facile construction of graphene based ultra folding resistance and high-efficiency electric heating film by multi-molecules induced orientation and interface regulation

Graphene (Gr) electrothermal film is a composite polymer conductive film that has garnered significant attention as a novel material due to its unique physical properties. However, the flexibility of the currently reported graphene electrothermal films is insufficient, and their preparation costs are relatively high. Additionally, the heat treatment process significantly influences the performance of these films. In this study, curcumin (CU) and carboxymethyl cellulose (CMC) were selected as dispersant and binder respectively, which synergistically induced graphene orientation and interface regulation with SiO₂ nanoparticles to construct highly flexible electrothermal film. CU contains hydroxyl groups and exhibits strong hydrogen bond interactions between molecules, which can enhance the interfacial compatibility of graphene paste and reduce graphene agglomeration. SiO₂ nanoparticles can be firmly anchored to the surface of graphene sheets through hydrogen bond interactions, effectively preventing aggregation. CMC has various bonding modes with Gr, which can facilitate film diffusion and significantly improve flexibility. During hydrolysis, CMC releases Na⁺, further stabilizing the dispersion of graphene. Simultaneously, an innovative film-laying process-suspension coating and casting method was employed to prepare large-area ultra-flexible graphene electrothermal films (HF-Gr/CMC). This process is straightforward and easy to implement without heat treatment, thus considerably reducing production costs while enabling potential for large-scale manufacturing. The obtained film demonstrates remarkable durability, which can be folded 180 degrees for 50,000 cycles while maintaining stable performance, significantly exceeding the reported folding resistance values of graphene based composite electrothermal films. The film also exhibits uniform heating temperature distribution with thermal radiation efficiency reaching 90.2 %, alongside impressive thermal conductivity measured at 83.76 Wm⁻¹ K⁻¹. These attributes provide a viable solution for ongoing enhancement and development in the field of graphene electrothermal films.