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[Display omitted] Both high through-plane thermal conductivity and low elastic modulus can reduce thermal interface resistance, which is important for thermal interface materials. The internal porous structure of graphene aerogel (GA) makes it to have a low elastic modulus, which results in its good compressibility. Also, the network structure of GA provides thermal conducting paths, which improve the through-plane thermal conductivity of GA. Annealing GA at 3000 °C helps to remove oxygen-containing functional groups and reduces defects. This greatly improves its crystallinity, which further leads to the improvement of its through-plane thermal conductivity and it has a low modulus of 1.37Mpa. The through-plane thermal conductivity of GA annealed at 3000 °C (GA-3000) was improved as the pressure increased and got to 2.93 W/ m K at a pressure of 1.13 MPa, which is 30 times higher than other graphene-based thermal interface materials (TIMs). These discoveries offer a novel approach for preparing excellent TIMs. [ABSTRACT FROM AUTHOR]

With the continuous advancement of electronic devices, there is an urgent need for advanced thermal interface materials (TIMs) to prevent high-power density electronics from overheating. The orderly arrangement of thermally conductive fillers in TIMs plays a crucial role in enhancing thermal conduction along preferred directions. However, it is challenging to control the orientation of the fillers, especially for two-dimensional fillers. In this study, graphene nanoplates (GNPs) were co-planarly arranged in polyvinyl alcohol (PVA) using a rotating magnetic field, which significantly increased the thermal conductivity of the composites. The coplanar vertically aligned GNPs/PVA (CVGNPs/PVA) exhibited a through-plane thermal conductivity of 11.78 W m−1 K−1, which is about 10 times higher than that of the composites with disorderly distributed GNPs (1.14 W m−1 K−1). The rotating magnetic field facilitated the alignment of GNPs and increased face-to-face contact between adjacent GNPs, which significantly boosted the through-plane thermal conductivity of the composite. The compressive modulus of the CVGNPs/PVA composites was only 1.06 MPa, and it helped to reduce the thermal interface resistance to 49 mm2 K W−1. These results offer a novel approach for preparing excellent TIMs that could be used in various applications. GNPs are oriented more compactly and orderly in PVA by using the rotating magnetic field, resulting in a densified thermal conductive paths and higher thermal conductivity of the composite. [Display omitted] [ABSTRACT FROM AUTHOR]

A review of carbon-based thermal interface materials: mechanisms, thermal measurements and thermal properties. [Display omitted] • Various carbon-based thermal interface materials were reviewed, ranging from one-dimensional carbon nanotubes, two-dimensional graphene films, to three-dimensional graphene foams, graphene aerogels, vertical graphene and other 3D graphene. • Thermal measurements for bulk and nanoscale materials were discussed to offer a guidance for improving the precision of the results. • The challenges for carbon-based thermal interface materials were discussed, including how to decrease the overall thermal resistance of thermal interface materials, the potential applications from micro to macro devices and the prerequisites for industrial application. With the development of electronic technologies, electronic devices become smaller, while their power density increases dramatically. The resulting excessive heat requires excellent heat dissipation to ensure great performance of the devices. A good thermal interface material (TIM), with excellent bulk thermal conductivity and proper elastic modulus, which can fill the gap between contact surfaces, is of great importance to improve overall performance of thermal management in the electronic devices. Carbon-based materials, such as carbon nanotubes (CNTs) and graphene (Gr), have attracted great attentions, due to their intrinsic high thermal conductivity. In this paper, carbon-based TIMs are reviewed, as well as the thermal conducting mechanisms and techniques to measure thermal properties for materials. The unique three-dimensional network of 3D-Gr provides not only high thermal conductivity, but also excellent mechanical properties, which makes it more competitive as TIM than CNTs and Gr. Furthermore, there is currently no universal characterization techniques, which are suitable to measure thermal properties of all TIMs. Hence, special attention must be paid to select a proper technique based on the measuring principle, in order to obtain accurate results. An outlook of the future challenges of the thermal interface materials is proposed at the end of the paper. [ABSTRACT FROM AUTHOR]