3D graphene and boron nitride structures for nanocomposites with tailored thermal conductivities: recent advances and perspectives

Abstract

Various three-dimensional (3D) structures are rationally assembled from two-dimensional (2D) nanosheets of graphene and boron nitride (BN) for thermal energy regulating applications. The nanocomposites containing these 3D architectures offer thermal conductivities spanning a few orders of magnitude from ultralow values for super thermal insulation to high values for fast heat dissipation. In this review, we summarize the approaches developed to achieve two extremes of thermal conductivity in 3D graphene and BN assemblies by engineering their structures at different length scales. A special focus is placed on identifying key structural parameters affecting the thermal conductivities, including pore morphologies, pore sizes, and cell wall structures. Distinctive applications of 3D graphene and BN structures and their polymer-based composites for thermal energy management are highlighted along with their potential multifunctionalities other than thermal conduction or insulation. The in-depth understanding of thermal transport properties offer insight into designing novel 3D structures that possess desired thermal conductivities for emerging thermal management applications.

Advances in Studies of Boron Nitride Nanosheets and Nanocomposites for Thermal Transport and Related Applications

“…Nevertheless, all things considered it seems that the sonication in IPA still represents a relatively easy option in this simple approach, by which BNNs of reasonable quality and solvent dispersion characteristics can be obtained for their uses in thermally conductive polymeric nanocomposites and related materials. [13,[18][19][20][21][22][23][24]33] In this exfoliation approach, the modifications aimed at enhancing the exfoliation efficiency or replacing IPA with some more complicated or costly solvent systems have generally been not exciting, with a few achieving somewhat improved outcomes, but hardly considered transformational. Other exfoliation approaches have attracted significant recent attention, in which the sonication in IPA or other solvents has been incorporated as a step in the overall exfoliation processing.…”

“…A major use of BNNs is in polymeric nanocomposites for thermal transport properties and others that take advantage of ChemPhysChem the mechanical and chemically stable characteristics. The focus here is on the former, [7,[13][14][15][16][17][18][19][20][21][22][23][24][25]33,95,102,112,133,[135][136][137][138] and those who are interested in the latter are referred to other reviews. [19,23,26,[267][268][269][270] As nanoscale fillers in polymeric nanocomposites, BNNs are unique for their high thermal conductivity but no electrical conductivity, particularly suitable for applications that require electrical insulation, thus beyond the reach of their carbon counterparts graphene nanosheets.…”

“…As a result, there have been more recent investigations on the development of thermally conductive polymer/BNNs nanocomposites for thermal management and related uses. [7,[13][14][15][16][17][18][19][20][21][22][23][24][25]33,95,102,112,133,[135][136][137][138]…”

“…BNNs retain the advantageous characteristics of h-BN, yet at the same time possess the desired features of nanomaterials, such as large 2D aspect ratios and solvent dispersibility, making BNNs excellent nanoscale fillers for polymeric nanocomposite materials. [6,7,[13][14][15][16][17][18][19][20][21][22][23][24][25] In fact, there have been extensive recent investigations on the development of polymer/BNNs nanocomposites for thermal management and other applications.…”

“…The excitement associated with the single‐ and multi‐layer graphene nanosheets has stimulated a similar intensive interest in few‐layer BN nanosheets (BNNs, Figure 1) [7] for their different properties from those of graphite and h‐BN, respectively. BNNs retain the advantageous characteristics of h‐BN, yet at the same time possess the desired features of nanomaterials, such as large 2D aspect ratios and solvent dispersibility, making BNNs excellent nanoscale fillers for polymeric nanocomposite materials [6,7,13–25] . In fact, there have been extensive recent investigations on the development of polymer/BNNs nanocomposites for thermal management and other applications.…”