Abstract In the present study, metal coated nanocapsules of ethyl stearate-ethyl palmitate eutectic phase change material (PCM) with high thermal conductivity were synthesized by in-situ emulsion polymerization followed by trisodium citrate reduction method. HRTEM analysis reveals the formation of core-shell structure with uniform spherical morphology and EDX results showed the presence of metal coating over silica shell. Phase change property of the eutectic mixture and nanocapsules were measured using DSC. Metal coated nanocapsules exhibited better thermal stability, conductivity and reliability determined by TGA, laser flash and thermal cycling analysis. Nanocapsules can persist constant phase change properties even after 1000 melting/ freezing thermal cycles. Most significantly, the thermal conductivity of metal coated nanocapsules increases from 0.257 ± 0.007 (eutectic mixture) to 0.660 ± 0.019, 0.693 ± 0.020 and 0.713 ± 0.021 Wm−1 K−1 for cobalt, copper and silver coated nanocapsules respectively. Similar to silver coated nanocapsules, copper and cobalt coated nanocapsules can also prove to be a promising material for thermal energy storage applications.

中文翻译：

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乙基酯脂肪酸共晶混合物的新型金属涂层纳米胶囊作为相变材料，具有增强的热导率，用于储能应用

摘要 本研究通过原位乳液聚合和柠檬酸三钠还原法合成了具有高导热性的硬脂酸乙酯-棕榈酸乙酯共晶相变材料(PCM)金属包覆纳米胶囊。HRTEM 分析揭示了具有均匀球形形态的核壳结构的形成，EDX 结果显示在二氧化硅壳上存在金属涂层。使用DSC测量共晶混合物和纳米胶囊的相变特性。通过 TGA、激光闪光和热循环分析确定，金属包覆的纳米胶囊表现出更好的热稳定性、导电性和可靠性。即使在 1000 次熔化/冷冻热循环之后，纳米胶囊仍能保持恒定的相变特性。最重要的是，金属包覆纳米胶囊的热导率分别从 0.257 ± 0.007（共晶混合物）增加到 0.660 ± 0.019、0.693 ± 0.020 和 0.713 ± 0.021 Wm-1 K-1，分别用于钴、铜和银包覆纳米胶囊。与银包覆纳米胶囊类似，铜和钴包覆纳米胶囊也被证明是一种有前途的热能储存应用材料。