In Situ Combustion Synthesis of Gr/h-BN Composites and Its Passive Heat Dissipation Application

Abstract

To enhance the infrared radiation efficiency and the heat transfer performance simultaneously, graphene (Gr) was synthesized in situ on hexagonal boron nitride (h-BN) to prepare Gr/h-BN composites by a scalable combustion synthesis in CO 2 atmosphere using Mg as sacrificial solder. The synthesized Gr/h-BN composites were added in polydimethylsiloxane polymer to prepare composite coatings, which show an infrared emissivity greater than 0.95 and a through-plane thermal conductivity up to 2.584 W•m −1 •K −1 . When functioning on an Al heatsink, such a composite coating can reduce the temperature by as much as 21.7 °C. Meanwhile, the composite coating exhibits superior adhesion on the Al substrate. Therefore, Gr/h-BN composite coatings with noteworthy infrared radiation and thermal conductivity are expected to be a promising candidate for heat dissipation applications.

Turning CO2 into sustainable graphene: a comprehensive review of recent synthesis techniques and developments

“…It becomes possible to enhance the heat transfer capabilities by incorporating CO 2 -derived graphene into thermal interface materials. Moreover, graphene/hexagonal boron nitride hybrid polymer composite with polydimethylsiloxane was prepared by manufacturing in CO 2 atmosphere, which show an infrared radiation higher than 0.95 and a through-plane thermal conductivity up to 2.584 W m −1 •K for heat dissipation applications [172]. In a study conducted by Liu et al, the graphene which has a thickness of 1-5 carbon layers was produced at small lateral dimension of 2-8 µm with electrochemical exfoliation of the platelets into graphene from CO 2 so as to demonstrate the implementation area of graphene-based lubricants in precision machinery and automotive engines [173].…”

“…The usage of CO2 derived graphene References Adsorption capacity Adsorbents for water purification, membrane filter [166][167][168][169][170][171] Composite materials in automotive and aerospace industry High-performance composite filler, energy efficiency in vehicle and aircraft components, coatings, lubricant and films, thermal management in heat dissipation [156,159,[172][173][174] Energy storage devices Rechargeable lithium-ion batteries, supercapacitors and capacitive deionization [8,[175][176][177] Photonics and quantum technologies Electronic industry Photocatalyst and sensors, flexible electronics, optoelectronic devices and sensors, enabling advancements in technology. In this context, significant advances and understanding of graphene-based semiconductors and their potential as promising candidates for solar fuel conversion draw attention to utilize electrochemical CO 2 capture technologies in the electric field with an effective and controllability strategy [178].…”

Effect of TiO2 on the thermal performance and emissivity of glass coatings

“…The total amount of heat dissipation could be determined by eqn (3). 13 P = P c + P r = k ( T 1 − T 2 ) + ε · σ · A ·( T 1 4 − T 2 4 )where P c represents the heat conducted from the coating to the air, P r is the heat radiated from the coating, k stands for thermal conductivity (W m −1 K −1 ), ε denotes the emissivity of the coating (0 ≤ ε ≤ 1), σ is the Stefan–Boltzmann constant (5.67 × 10 −8 W m −2 K −4 ), A is the coating's surface area (m 2 ), T 1 represents the sample's temperature (K), and T 2 is the air temperature (K).…”

Enhancing the thermal shock and corrosion resistance of low‐carbon Al2O3–C refractories: The role of h‐BN composite powder

“…14,15 The h-BN material exhibits several advantages, including high thermal conductivity, low thermal expansion coefficient, and excellent machinability. 16,17 Its nonwettability and resistance to molten steel make it an ideal alternative to graphite. Moreover, h-BN is more oxidation resistant than graphite and does not react with antioxidants.…”

“…Currently, graphite is the primary source of carbon used, however, hexagonal boron nitride (h‐BN) garnered attention due to its structural similarity to graphite 14,15 . The h‐BN material exhibits several advantages, including high thermal conductivity, low thermal expansion coefficient, and excellent machinability 16,17 . Its nonwettability and resistance to molten steel make it an ideal alternative to graphite.…”