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强化熔融盐的比热容对降低太阳能热发电的发电成本非常有利.采用两步水溶液法制备了以三元碳酸盐K2CO3-Li2CO3-Na2CO3 (4∶4∶2质量比)为基盐,SiO2(5 nm、10 nm、15 nm、20 nm、30 nm、60 nm)为添加剂的三元碳酸盐纳米流体,对其比热容进行了分析,并讨论了比热容提高机制.结果表明,添加小于30 nm SiO2的熔盐纳米流体,除10 nm SiO2,比热容提高量相当.而对于添加大粒径60 nm SiO2的熔盐纳米流体的比热容的提高量明显的降低.此外,三元碳酸盐纳米流体的比热容在热循环30次内具有较好的稳定性.添加纳米颗粒后的三元碳酸盐纳米流体的分解温度仍高达853.9℃.三元碳酸盐纳米流体中产生的纳米结构可能是比热容提高的主要机制.“,”Enhancing the specific heat capacity of molten salt is very beneficial to reduce the cost of generation electricity of solar thermal power.In the present work, ternary carbonates nanofluids of K2CO3-Li2CO3-Na2CO3 (4∶4∶2, mass ratio) with SiO2 (5 nm, 10 nm, 15 nm, 20 nm, 30 nm, 60 nm) nanoparticles were prepared by using a two step solution method.The specific heat capacities of sample are measured, and the mechanism is discussed.The results indicates that the specific heat capacities of ternary carbonates nanofluids with SiO2 (5 nm, 15 nm, 20 nm, 30 nm) increases at around the same level.However, the enhancement of ternary carbonates nanofluids with SiO2 (60 nm) significantly decreases.Moreover, the specific heat capacity of ternary carbonates nanofluids remains stable during thermal cycling in thirty times.The decomposition temperature of ternary carbonates nanofluids is up to 853.9℃.The nanostructures formed in ternary carbonates nanofluids may be the main mechanism responsible for the enhanced specific heat capacity.