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• GFs were integrated with ANF through sol-hydrogel-paper process. • GF/ANF paper possess thermally conductive yet electrically insulating property. • Vibrational properties of GF and ANF were studied using ab initio calculation. • Superb mechanical properties with a remarkable toughness and strength were achieved. • Excellent thermal stability and nonflammability were obtained. Heat dissipation is a critical requirement for the innovation of fifth-generation (5G) electronics, and in turn, for the unceasing development of highly efficient heat-dissipating materials (HDMs). In 5G electronics, high thermoconductive yet electrically insulating HDMs with lightweight, excellent flexibility, and outstanding thermal properties have a high demand. In this study, we developed a fabulous HDM with superior mechanical properties, high thermal conductivity, and electrical insulation. The underlying principle involves taking advantage of graphene fluoride (GF), which is an emerging two-dimensional (2D) material that is highly thermally conductive, along with an electrically insulating material. By integrating a 2D GF sheet in a three-dimensional (3D) interconnected aramid nanofiber (ANF) network, a paper was successfully fabricated via a scalable process of sol-hydrogel-paper transformation. The resultant GF/ANF paper showed excellent mechanical properties with a remarkable strength of 188 MPa and toughness of 107 MJ m−3. These exceptional results are attributed to the formation of a nacre-inspired structure with strong hydrogen bonding between the GF sheet and ANF matrix and the extensive elongation of the entangled 3D ANF. Notably, the GF/ANF nacre-inspired paper with 40 wt% GF content achieved a thermal conductivity and volume resistivity as high as 48.2 W m−1 K−1 and 2.7 × 1015 Ω m, respectively. Moreover, the vibrational properties of GF and ANF were extensively investigated via ab initio calculations. The paper exhibited excellent thermal stability, non-flammability, and high efficiency in heat dissipation in an organic light-emitting diode system. It demonstrated the best overall performance among the representative HDMs analyzed, representing a critical breakthrough in the fabrication of HDMs toward practical applications in wearable electronic devices. [ABSTRACT FROM AUTHOR]

Thermally conductive electromagnetic interference (EMI) shielding materials with excellent thermal conductivity, EMI shielding effectiveness (SE), and electrical insulation are pivotal for ensuring the operation and performance of next-generation electronic devices, safeguarding them against external electromagnetic waves and mitigating excessive heat generation. In this study, multilayered graphene fluoride (GF) and Ti 3 C 2 T x MXene (MX)-based aramid nanofiber (ANF) films, in which the MX@ANF layer was sandwiched between GF@ANF layers, were fabricated using the alternating vacuum filtration method. The resultant multilayered films with increased GF and MX contents showed an upsurge in thermal conductivity and EMI SE while maintaining excellent electrical insulation, thermal stability, and mechanical flexibility. The GF50/MX75 film with 50 wt% GF content and 75 wt% MX content in each layer exhibited an excellent EMI SE of ∼41 dB in the X-band frequency, along with a superior specific shielding effectiveness of 3818 dB·cm2/g, an outstanding in-plane thermal conductivity of 85 W/m·K, and mechanical strength of 70 MPa. The notable properties of the GF/MX films are attributed to the well-ordered alignment of the GF and MX sheets and their strong interaction with ANF, which facilitates phonon and electron conduction. Furthermore, the multilayered GF/MX films exhibited excellent heat dissipation capabilities and flame retardancy. Owing to their exceptional performance, multilayered GF/MX films offer a compelling opportunity to advance EMI shielding and thermal management materials to the forefront of next-generation electronics. [Display omitted] • Multilayered GF and MX-based ANF films were fabricated using sequential vacuum filtration method. • Prepared GF50/MX75 film exhibited exceptional EMI SE of ∼41 dB and in-plane thermal conductivity of 85 W/m·K. • Well-ordered alignment of GF and MX sheets with ANF facilitates effective phonon and electron conduction. • Multifunctional GF50/MX75 films have significant potential for heat dissipation and EMI shielding in next-generation electronic devices. [ABSTRACT FROM AUTHOR]