Thermal characteristics enhancement of Paraffin Wax Phase Change Material (PCM) for thermal storage applications

Abstract

This study investigates the integration of graphene nanoplatelets and nano SiO2 into paraffin wax to enhance its thermal energy storage capabilities. Dispersing graphene nanoplatelets and nano SiO2 nanoparticles at weight percentages of 0.5 and 1.0 respectively, in paraffin wax yielded mono and hybrid phase change materials (HYB). Transmission electron microscopy, Field Emission Scanning Electron Microscopy and X-ray diffraction were used to determine the size and phases of secondary particles of graphene nanoplatelets and nano SiO2. Differential Scanning Calorimetry, Thermogravimetric Analysis and Thermal Conductivity Measurement were employed to investigate the impact of hybrid nanoparticles on thermo physical characteristics of paraffin wax. The weight fraction of nano particles distributed in the PCMs is directly related to the enhancement of thermal conductivity of hybrid PCM. The highest enhancement in thermal conductivity was observed when hybrid nanoparticles were present at a weight fraction of 1 %. The analysis shows that mixing graphene nanoplatelets and nano SiO2 with paraffin wax was uniform and the hybrid nanoparticles boosted its thermal conductivity by 38 %, 42 %, and 50 %, respectively. Experimental evidence indicate that the addition of nanoparticles can decrease the melting temperature and increase the solidification temperature of hybrid phase change materials (PCMs). When dispersed in large quantities, nanoparticles can alter properties like latent heat, specific heat, and viscosity. These promising findings suggest that graphene nanoplatelets and nano SiO2 can enhance paraffin wax's thermal properties for thermal storage application.