Effects of silica nanoparticles on enhancing the specific heat capacity of carbonate salt eutectic (work in progress)

Abstract

Nanomaterials were obtained by dispersing silica nanoparticles in eutectic salt mixtures. The synthesis protocol was varied to obtain different nanomaterial samples of the same composition but different morphologies. The synthesis protocols that led to agglomerated nanoparticles resulted in coarse powders (Type-A samples) and the protocols that led to (un-agglomerated) well dispersed nanoparticles resulted in fine grained powders (Type-B samples). Measurements using differential scanning calorimeter (DSC) showed that the average specific heat capacity of the Type-A samples was enhanced by ~20 % (solid phase) and ~75 % (liquid phase); while that of Type-B samples was enhanced by ~34 % (solid phase) and ~100 % (liquid phase). Electron microscopy of the samples revealed that the variation in the thermophysical properties of the different samples was caused by the amount of the agglomeration of the nanoparticles as well as the formation of compressed phase. This study shows that these nanomaterials can enable significant reduction in the cost of solar thermal power.