Abstract
The enhancement of phase change materials (PCMs) by adding nanoparticles presents a potential option for improving thermal energy storage (TES) systems. This study investigated the thermal performance of eicosane PCM nanoemulsions improved with multi-walled carbon nanotube (MWCNT) introduced at different stages of the preparation process. Besides, the research examines the impact of MWCNT addition timing on the thermal properties and dispersion stability of the resulting nanoemulsions. As a result, the optimal composition was determined to be MWCNT@PCM-ED, with MWCNT and PCM concentrations of 0.2 wt% and 50 wt%, respectively. The results show that the timing of MWCNT addition significantly impacts the thermal characteristics of the PCM nanoemulsions. PCM emulsions with MWCNTs added during pre-emulsification exhibited the highest improvement in thermal characteristics, while those with post-emulsification addition showed relatively lower enhancement. The degree of supercooling in MWCNT@PCM-ED, consisting of 0.2 wt% MWCNT and 50 wt% eicosane, was reduced from 8 to 0.4 °C compared to pure eicosane PCM. However, the latent heat of fusion for MWCNT@PCM-ED decreased from 251.3 to 138.5 J/g relative to pure eicosane PCM. These results are crucial for developing high-performance PCM nanoemulsions for TES applications.
