Tailoring Dense, Orientation-Tunable, and Interleavedly Structured Carbon-Based Heat Dissipation Plates

Current research in thermal conductivity optimization often focuses on material alignment and microstructure control. Prior studies have demonstrated that vertically aligned carbon nanotubes (CNTs) can enhance heat transfer properties. However, the challenge of maintaining orientation during compression remains unresolved. Existing methods struggle to preserve the vertical alignment of CNTs when compressed into dense structures. This gap motivated the exploration of new fabrication techniques that preserve ordered microstructures. No prior work had resolved how to maintain perpendicular alignment during compression. The need for better thermal dissipation in high-power electronics drives this research. Conventional materials like Si₃N₄ show limited performance in heat dissipation. This study addresses the need for orientation-tunable structures.

The aim of this study is to investigate how ordered microstructures affect thermal conductivity in compressed carbon-based materials. The specific problem is the loss of vertical alignment during compression, which degrades heat dissipation performance. The motivation comes from the need for efficient cooling in high-power LED applications. The researchers propose a new fabrication approach using interleaved structures. This method aims to preserve the ordered arrangement of carbon nanotubes during compression. The study compares two types of structures: O-VA-GF and S-VA-GF. The goal is to determine how microstructure control influences thermal conductivity. The findings may lead to improved heat dissipation materials for electronics.

The researchers fabricated two types of compressed building blocks: O-VA-GF and S-VA-GF. These structures combine vertically aligned carbon nanotube arrays with graphene films. The fabrication process involves compression molding of these 3D core-ordered materials. The O-VA-GF structure preserves vertical alignment during compression. In contrast, the S-VA-GF structure experiences horizontal collapse of nanotubes. Thermal conductivity was measured in both through-plane and in-plane directions. The study used standard thermal testing protocols to compare performance. The materials were tested as heat dissipation plates in LED cooling applications.

The O-VA-GF structure achieved a through-plane thermal conductivity of 41.7 W m⁻¹ K⁻¹. The in-plane thermal conductivity reached 397.9 W m⁻¹ K⁻¹. These values outperformed the S-VA-GF structure, which had 10.3 W m⁻¹ K⁻¹ through-plane and 240.9 W m⁻¹ K⁻¹ in-plane. The ordered structure provided a 144% improvement in cooling coefficient over Si₃N₄. The interleaved design preserved vertical alignment during compression. The study showed that orientation control significantly affects thermal performance. The results suggest that ordered microstructures enhance heat dissipation efficiency. The findings support the hypothesis that microstructure design impacts thermal conductivity.

The authors conclude that ordered microstructures in compressed carbon-based materials improve thermal performance. The study shows that preserving vertical alignment during compression enhances heat dissipation. The O-VA-GF structure outperformed the S-VA-GF in both through-plane and in-plane conductivities. The results suggest that interleaved structures are effective for thermal management. The researchers propose that this method could be used in high-power LED cooling applications. The findings indicate that orientation-tunable structures are beneficial for thermal conductivity. The study supports the idea that microstructure design influences material performance. The authors suggest that this approach could lead to better heat dissipation materials.