Preparation and Characterization of Capric-Lauric Acid/Silicon Dioxide Nanocapsules as Phase Change Energy Storage Materials

Abstract

Capric acid (CA)-lauric acid (LA)/silica (SiO2) nanocapsules were fabricated in this paper. The core material was acted by CA-LA eutectic mixture, and the shell material was supported by SiO2. The phase identification, chemical composition, micrograph, and thermal property of as-prepared samples were analyzed based on X-ray diffraction, Fourier transformation infrared spectroscope, Scanning electron microscope and Differential scanning calorimety, respectively. These results displayed that CA-LA eutectic mixture was well encapsuled into SiO2 pore network. The CA-LA/SiO2 nanocapsules were spherical with uniform particle size of about 100 nm. When the mole proportion of CA:LA was 65:35, the phase transition temperature of nanocapsules was measured as 18.98 °C, and latent heat was confirmed as 83.06 J/g. The phase change temperature of the nanocapsules was basically consistent with the calculation value of pure CA-LA eutectic, and latent heat was about 58% of the theoretical value, signifying a high encapsulation efficiency. Therefore, CA-LA/SiO2 nanocapsules as PCMs could provide thermal energy storage for buildings.