Depression of melting point and latent heat of molten salts as inorganic phase change material: Size effect and mechanism

The depression of melting point and latent heat is a common phenomenon for nanoporous shape-stabilised phase change materials (ss-PCMs), however, the underlying mechanism not well understood, especially from microscopic perspective. As PCMs are embedded in nanopores, thermal properties may be due to size effect, interaction effect or both. In this paper, on was studied using molecular dynamics simulation explored. NaCl selected as PCM nanoparticle 2 nm 9 nm. Bulk molten salt also simulated validate correctness results. It found that atoms smaller nanoparticles vibrate more intensely so crystal structure easier destroyed, leading lower point. coordination number indicates loosely packed structure. Thus, less energy required destroy crystalline lattice decreased. This paper reveals atomic view paves way further studying nanopores.