Preparation and investigation of distinct and shape stable paraffin/SiO2 composite PCM nanospheres

The synthesis of a shape stable paraffin/SiO2 composite PCM, for use in latent heat storage, comprised of distinct nanospheres, using a novel and simple chemically aided infiltration method was investigated and the produced samples were characterized. SiO2 spheres were synthesized, with the sol-gel method, and then used to encapsulate paraffin wax using several different preparation ratios of paraffin to SiO2. The samples' constitution and morphology were characterized by FT-IR spectroscopy and scanning electron microscopy (SEM) respectively. Thermogravimetric analysis (TGA) was used for the paraffin mass percentage determination. The results were indicative of paraffin encapsulation inside the porous network of the SiO2 spheres. DSC was used to investigate the thermophysical properties of the composite samples and for their evaluation as PCMs. The sample with the highest encapsulation ratio (B4 at 78.15%) had a paraffin mass percentage of 80% and a latent heat of similar to 156 J/g. The encapsulation's influence on paraffin's thermal properties was investigated and an optimum preparation ratio was determined. The composite nanoparticles retained a large amount of the paraffin's latent heat while showing no signs of aggregation-a novelty for paraffin/SiO2 nanoPCM- and presenting enhancements that make them promising materials for heat storage applications (LHTES).