Hybrid Graphene Nanocomposites: Thermal Interface Materials and Functional Energy Materials

Abstract

Most existing materials may not satisfy all the fundamental requirements of modern civilization. This chapter summarizes the latest advances in the study of hybrid graphene nanocomposites and their application as thermal interface materials and some functional energy materials, in particular, for thermal management of energy and electronic devices. The main properties of hybrid graphene nanocomposites are described. The main attention is paid to the thermal properties of such materials, in particular, thermal conductivity and the possibilities of its growth due to various changes in the morphology and other properties of nanocomposites. The technology of obtaining a new nanocomposite based on mesoscopic microspheres, polymers, and graphene flakes is considered.

On thermal problems of the solar thermal multigeneration: new nanomaterials and working fluids

“…In recent years, interest in solar thermal power engineering based on new materials and technologies has sharply increased [1][2][3][4][5][6]. The efficiency of various types of generation due to the conversion of solar radiation of the Planck spectrum is largely related to both the use of conversion technologies (steam generation -volumetric and surface with subsequent conversion of steam through machine (turbine) and electric generator conversion), and the thermoelectric generation, i.e., conversion of solar radiation heat with a high degree of its absorption in nanomaterials due to the use of modern and promising materials with high quality factor, as well as with hybrid conversion of solar radiation (part -photoelectric conversion, part -steam generation due to heating by Planck spectrum radiation, followed by thermoelectric or steam generation).…”

“…Figure 4. Steam generation processes using nanoplasmonics and nanophotonics [1,6] The plasmon resonance wavelength can be controlled depending on the composition, size, geometry, the width of the gap between the nanoparticles and the type of environment. The generation of vapor upon heating of nanocomponents by solar radiation (nanoparticles of noble metals, nanodiamonds, graphene flakes, etc.…”

Active thermal interface graphene nanocomposites for thermal control of electronic and power devices

“…The development of modern and promising electronic and energy devices requires ever more efficient thermal control systems for thermal stabilization and management of thermal conditions [1,2]. Until now, thermal control systems have been divided into two broad categories.…”

“…However, recent developments of new nanomaterials, including graphene, graphene nanocomposites and other two-dimensional materials (boron nitride, aluminum nitride, molybdenum disulfide, etc.) allow developing and creating active thermal interface materials (active TIM), which simultaneously reduce thermal boundary resistance (Kapitza resistance at interfaces of various materials), and cool such interfaces due to either microchannel or evaporative cooling [1]. A significant step towards the creation of active TIM was the discovery of non-trivial capillary hydrodynamics of working fluids, in particular, water, inside porous graphene nanocomposites, which enables their quick delivery to the evaporation surface through the quasi-laminar structure of graphene nanoclaps [2][3][4][5][6].…”

“…In this work, we experimentally and theoretically investigate the main processes in active TIM, including thermohydrodynamics of flow and heat transfer inside quasi-laminar structures of graphene nanoflakes with different numbers of monoatomic thickness of graphene plates and study the processes of surface evaporation from graphene nanocomposites in a wide range of temperatures from room temperature up to Leidenfrost temperature and above. It is shown that the fast flow of water and other working fluids is associated with nontrivial capillary hydrodynamics of the non-Poiseuille type, and heat transfer inside such structures is associated with efficient heat transfer (low boundary thermal resistance between graphene nanoflatter and fluid flows due to a sharp increase in the velocity of fluid sliding along the surface -the Navier effect in the hydrodynamics of nanostructures [1]). The processes of wetting and evaporation of droplets of working fluids are investigated in different temperature ranges, and the dependences of the droplet evaporation rates on the heterogeneity and roughness of the surface are shown, which is important for the correct choice of technologies for the manufacture of new materials for active TIM.…”