Thermophysical characteristics and enhancement analysis of carbon-additives phase change mono and hybrid materials for thermal management of electronic devices

A novel zero-noise and clean thermal management technology (TMT), based on phase-change thermal energy storage (TES) technology, has turned out the new vision for researchers and industrialist involved in electronics industry. Therefore, this paper highlights a new direction by developing the nano-enhanced phase change materials (NePCMs) by combining the carbon-additives with phase change material. Four different types of carbon-additives of multi-wall carbon nanotube (MWCNT), graphene oxide (GO), reduced graphene oxide (rGO) and graphene nanoplatelet (GNP) were dispersed in RT-35HC, used as a PCM, with the combinations of mono (MWCNT, GO, rGO and GNP) and hybrid (GO+MWCNT, rGO+MWCNT and GNP+MWCNT) nanoparticles. A constant mass percentage of 1.0 wt.% was selected for both mono and hybrid combinations of nanoparticles to explore the best type and dispersion scheme for productive and effective thermal management applications. All the synthesized NePCMs were characterized using various characterization methods to study microstructural features, surface chemistry, lattice dimensions, stability, thermal and phase-change TES characteristics. The key findings reveal the best chemical and thermal stability, uniform dispersion of carbon-based nanoparticles in RT-35HC without modifying the molecular structure. The highest thermal conductivity enhancements of 182.7%, 183.8% and 185.3%, and optimum value of enthalpy of fusions of 237.42, 235.35 and 230.82 J/g were achieved for hybrid NePCMGO+MWCNT, NePCMrGO+MWCNT, and NePCMGNP+MWCNT, respectively in comparison of mono NePCMs. The phenomenon of thermal conductivity and specific heat capacity were explained systematically. Conclusively, the minimum subcooling, specific heat capacity enhancement and smaller phase-transition temperature reveal that GNP+MWCNT dispersed hybrid NePCM can be potentially used for thermal management applications.