Composite Interfaces, Vol.28, No.2, 175-189, 2021
Hydrophilic modification of carbon nanotube to prepare a novel porous copper network-carbon nanotube/erythritol composite phase change material
Carbon nanotube(CNT)-based materials is a promising thermally conductive filler for phase change materials(PCM), while its widely applications are greatly hampered by the hydrophobicity of CNTs. In this work, a novel composite PCM based on hydrophilic modified porous copper network(PCN)-CNT filler and erythritol(Ery) was explored. The hydrophilic modified PCN-CNT filler can be obtained upon heat treatment. During the heat treatment process, defects and oxygen-containing functional groups formed on the surface of CNTs, thus improving the hydrophilicity of CNTs. The optimum heat treatment temperature is determined to be 500 degrees C, at which the adsorptive capacity of the modified filler reaches 88.2% for Ery, larger than 28.2% of the unmodified one. The as-prepared PCN-CNT/Ery composite PCM maintains a similar melting point to that of pure Ery, and its latent heat is as high as 213.2 J g(-1). The thermal conductivity of PCN-CNT/Ery composite PCMs increases by 892% and 51% compared with pure Ery and PCN/Ery composite PCM, respectively. Moreover, the PCN-CNT filler could help improve the supercooling of Ery significantly. Besides, the enthalpy loss of the composite PCM was negligible after 20 cycles.