Implication of Size-Controlled Graphite Nanosheets as Building Blocks for Thermal Conductive Three-Dimensional Framework Architecture of Nanocarbons

ABSTRACT

Preparation of three-dimensional (3D) networks has received significant attention as an effective approach for applications involving transport phenomena, such as thermal management materials, and several nanomaterials have been examined as potential building blocks of 3D networks for the improvement of heat conduction in polymer nanocomposites. For that purpose, nanocarbons such as graphene and graphite nanoplatelets have been spotlighted as suitable filler materials because of their excellent thermal conductivities (ca. 10²–10³ W·(m·K)⁻¹ along their lateral axes) and morphological merits. However, the implications of morphological features such as the lateral length and thickness of graphene or graphene-like materials have not yet been identified. In this study, a controlled dissociation of bulk graphite to graphite nanosheets (GNSs) using a low-cost, ecofriendly bead mill process was extensively examined and, when configured in a 3D framework architecture formation, the size-controlled GNSs demonstrated that the thermal conductivities of a 3D interconnected framework of GNSs and the corresponding polymer nanocomposite were intimately correlated with the size of the GNSs, thus demonstrating the successful preparation of an efficient thermal management material without highly sophisticated efforts. The capability of controlling the lateral size and thickness of the GNSs as well as the use of a 3D interconnected framework architecture should greatly assist the commercialization of high-quality graphene-based thermal management materials in a scalable production process.

KEYWORDS:

• Graphite nanosheets
• three-dimensional framework architecture
• nanocomposite
• thermal conductivity
• size control

Additional information

Funding

This work was kindly supported by a grant (Code No. 2011-0032156) from the Center for Advanced Soft Electronics under the Global Frontier Research Program of the Ministry of Science, ICT & Future Planning, Korea, and the R&D Convergence Program of NST (National Research Council of Science and Technology), Korea. This research was also supported by Hallym University Research Fund, 2017 (HRF-201703-005), and Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2017R1D1A3B03030562). S.-S. Lee also appreciates the research grant from the KU-KIST Graduate School and the internal project of KIST.