Thermal transport properties of composite phase change materials characterized by molten carbonate-ceramic date nucleus occupancy structure: A molecular dynamics study

Abstract

Carbonate molten salts play a crucial role in energy transmission and storage for concentrated solar power (CSP) plants. In this study, a design strategy employing a date nucleus occupation structure was proposed for carbonate molten salt/ceramic SiO2 composite phase change materials (PCMs). Molecular dynamics (MD) simulations were conducted to investigate the thermal transport properties and nanoscale atomic structure of the Nanocomposite phase change materials (NPCM) system. The findings revealed that the incorporation of SiO2 nanoparticles significantly reduced the melting point of NPCM system, offering a favorable way to regulate the operating temperature range of the system. Moreover, the thermal conductivity and specific heat capacity of NPCM system increased with the increase in the radii of nanoparticles, reaching up to 12.32% and 6.061%, respectively. However, it was observed that larger nanoparticles limited the migration of particles, leading to a decrease in the self-diffusion coefficient (D) of the system. This study provides valuable insights in the design and application of CSP power plants utilizing nano-phase change materials.