A solar-thermal energy harvesting scheme: enhanced heat capacity of molten HITEC salt mixed with Sn/SiOx core–shell nanoparticles†
We demonstrated enhanced solar-thermal storage by releasing the latent heat of Sn/SiOx core–shell nanoparticles (NPs) embedded in a eutectic salt. The microstructures and chemical compositions of Sn/SiOx core–shell NPs were characterized. In situ heating XRD provides dynamic crystalline information about the Sn/SiOx core–shell NPs during cyclic heating processes. The latent heat of ∼29 J g−1 for Sn/SiOx core–shell NPs was measured, and 30% enhanced heat capacity was achieved from 1.57 to 2.03 J g−1 K−1 for the HITEC solar salt without and with, respectively, a mixture of 5% Sn/SiOx core–shell NPs. In addition, an endurance cycle test was performed to prove a stable operation in practical applications. The approach provides a method to enhance energy storage in solar-thermal power plants.