3D Network of Liquid Metal‐Embedded Graphene via Surface Coating for Flexible Thermal Management

• Published in: Small (Weinheim an der Bergstrasse, Germany) Germany), 2024-12, Vol.20 (50), p.e2406574-n/a
• Main Authors: Luo, Wenmei, Wei, Baojie, Luo, Tianlin, Li, Baowen, Zhu, Guimei
• Format: Article
• Language: English
• Subjects: Biosensors; flexibility; Flexible components; Graphene; graphene nanosheets; Heat transfer; liquid metal; Liquid metals; Modulus of elasticity; Thermal conductivity; Thermal management; Wearable technology
• ISSN: 1613-6810; 1613-6829; 1613-6829
• DOI: 10.1002/smll.202406574

The rapid growth of flexible electronics has led to significant demand for relevant accessories, particularly highly efficient flexible heat dissipators. The fluidity of liquid metal (LM) makes it a candidate for realizing flexible thermal interface materials (TIMs). However, it is still challenging to combine LM with a conductive thermal network to achieve the synchronous improvement of thermal conductivity and flexibility. In this work, highly conductive flexible LM@GN/ANF films are made by coating LM nano‐droplets with graphene nanosheets (GN) via sonication, and then they are combined with aramid nanofibers (ANF). The LM@GN/ANF film is found to have a thermal conductivity of 5.67 W m−1 K−1 and a 24.5% reduction in Young's modulus, making it suitable for various flexible electronic applications such as wearable devices and biosensors. LM nano‐droplets are coated by GN, enhancing the binding of LM and ANF and the stability of LM nano‐droplets. LM@GN form a uniformly distributed thermal conductive network, achieving a thermal conductivity of 5.67 W·m−1·K−1. The deformability of LM and the interaction between GN and ANF improve the flexibility of the film, resulting in a 24.5% decrease in Young's modulus.