Anisotropically Oriented Carbon Films with Dual‐Function of Efficient Heat Dissipation and Excellent Electromagnetic Interference Shielding Performances

Abstract

The rapid development of next‐generation portable electronic devices urgently requires dual‐functional materials that possess both efficient heat dissipation and outstanding electromagnetic interference (EMI) shielding performances. In this study, anisotropically oriented carbon films with high thermal conductivity and excellent EMI shielding properties are prepared through an innovative glucose hydrogel‐controllable carbonization method. The horizontal alignment of nanocrystalline graphite results in oriented structures with an extremely high in‐plane thermal conductivity of 439.9 W m−1 K−1, exhibiting a more effective heat‐dissipating capacity on smartphones than their commercial graphite counterparts. Additionally, owing to multiple internal reflections arising from the oriented structures, the films exhibit an EMI shielding effectiveness (SE) of 21.72 dB at an ultrathin thickness of 480 nm in the X‐band and an extraordinarily high absolute shielding effectiveness (SSE/t) of 275 883 dB cm2 g−1, significantly outperforming most of the reported synthetic materials. Furthermore, the flexibility, high mechanical strength, and stability of the films are demonstrated and therefore show promising application prospects. This study offers a facile yet feasible strategy for preparing dual‐functional materials to address the heat emission and EMI problems of advanced electronic devices in a more economical and environmentally friendly manner.

Flexible Large-Area Graphene Films of 50–600 nm Thickness with High Carrier Mobility

“…2 b and S5) plots show that PAN/GO systems have almost identical weight loss irrespective of the heating atmosphere, indicating that the GO/PAN system pre-oxidation occurs through self-oxygenation without external oxygen input [ 19 ]. A possible reason is that the dense 2D planar structure of GO and the high inner pressure caused by the release of gases inside the material prevent oxygen penetration from the external source [ 15 ]. The uniform dispersion of GO sheets and self-oxygenation effect endow the pre-oxidized GO/PAN system with a uniform oxygen distribution in a 3D structure (100 μm × 100 μm × 300 nm) with a stable oxygen intensity of 2 × 10 4 in time-of-flight secondary ion mass spectrometry (ToF–SIMS, Fig.…”

“…The EMI shielding performance was calculated based on S parameters (S 11 and S 21 ); the transmission power (T; T =|S 21 | 2 ), reflectivity power (R; R =|S 11 | 2 ), and absorption power (A; A + R + T = 1) [ 14 , 15 ].…”

Multifunctional CoFe2O4@MXene-AgNWs/Cellulose Nanofiber Composite Films with Asymmetric Layered Architecture for High-Efficiency Electromagnetic Interference Shielding and Remarkable Thermal Management Capability

“…With the flourishing growth of information technology, especially the explosive advance of miniaturized, highly integrated and high-power electronic devices in the fifth-generation communication era, serious electromagnetic interference (EMI) radiation pollution and undesirable heat accumulation are inevitably generated during operation. − Overheating and ubiquitous EMI pollution not only deteriorate the dependability and lifetime of equipment, but also have an adverse effect on human health. − Meanwhile, the booming spread of portable and wearable electronic devices proposes more flexible and thinner requirements for materials. − To effectively mitigate the EMI radiation and dissipate the accumulative heat for next-generation smart electronics, exploring ultrathin and flexible materials with high EMI shielding effectiveness (SE) and excellent thermal conductivity (TC) is urgently required.…”

Design of Interconnected Carbon Fiber Thermal Management Composites with Effective EMI Shielding Activity

“…The miniaturization of devices calls for rapid heat dissipation, which constrains their operational stability and service life . Polymer-based thermal conductive composites with flexible designability and excellent processability have become the best choice to improve the heat dissipation performance of electronic devices .…”

“…The miniaturization of devices calls for rapid heat dissipation, which constrains their operational stability and service life. 1 Polymer-based thermal conductive composites with flexible designability and excellent processability have become the best choice to improve the heat dissipation performance of electronic devices. 2 The arranging orientation of a heat-conducting filler along the direction of heat flow driven by an external force field can further enhance the heat dissipation effect of composites.…”