As　a　new　type　of　heat　storage　and　heat　transfer　medium,　molten　salt　has　been　widely　used　in　concentrating　solar　power　(CSP)　system　due　to　its　wide　working　temperature　range,　relatively　high　specific　and　strong　heat　storage　capacity.　Increasing　the　specific　heat　capacity　of　the　molten　salt　can　significantly　increase　its　heat　storage　density.　Nanofluids　were　synthesized　by　dispersing　20　nm　SiO2　and　MgO　particles　to　binary　carbonate　eutectic　(Li2CO3and　K2CO3).　The　specific　heat　capacity　effect　of　nanoparticles　on　molten　salt　was　characterized　by　DSC　measurement.　Results　show　that　mass　fraction　of　20　nm　nanoparticles　significantly　enhanced　the　specific　heat　of　binary　carbonate　eutectic.　Compared　with　the　base　salt,　the　average　specific　heat　improved　with　20　nm　MgO　and　SiO2　nanoparticles　was　found　to　be　27.5%-34.1%,　11%-20.7%,　respectively.　The　change　rate　of　the　specific　heat　values　of　the　two　nanofluids　is　lower　than　4.31%　after　multiple　solid-liquid　cycles.　The　molten　salt　nanofluids　showed　good　thermalstability.The　microstructure　of　nanofluids　was　characterized　by　scanning　electron　microscopy　(SEM).　The　images　of　nanofluids　in　solid　state　showed　that　special　nanostructures　were　formed　on　the　surface　of　molten　salts.　©　All　Right　Reserved.