Abstract Renewable energy has become of great interest over the past years in order to mitigate Global Warming. One of the actions gaining attention is the enhancement of the thermal energy storage capacity of Concentrated Solar Power plants. The addition of nanoencapsulated phase change materials (core-shell nanoparticles) to the already used materials has been proposed for that purpose, due to the possibility of increasing thermal storage through the contribution of both core latent heat and sensible heat. In this work, Atomic Layer Deposition has been used to synthesise SiO2 and Al2O3 nanoscale coatings on tin nanoparticles. The multi-encapsulated phase change materials have been characterised in terms of chemical composition, crystalline structure, particle size, thermal stability and thermal storage capacity. Sn@Al2O3 nanoparticles present the best thermal behaviour as they show the lowest reduction in the phase change enthalpy over 100 cycles due to the oxidation barrier of the coating. Moreover, the specific heat of both nanoparticles and solar salt-based nanofluids is increased, making the nanoencapsulated phase change material suitable for thermal energy storage applications.

中文翻译：

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通过原子层沉积改进纳米封装相变材料的热能储存

摘要 在过去的几年中，可再生能源已成为缓解全球变暖的极大兴趣。备受关注的举措之一是提高聚光太阳能发电厂的热能储存能力。出于该目的，已提议将纳米封装相变材料（核壳纳米粒子）添加到已使用的材料中，因为通过核潜热和显热的贡献增加热存储的可能性。在这项工作中，原子层沉积已被用于在锡纳米颗粒上合成 SiO2 和 Al2O3 纳米级涂层。多封装相变材料在化学成分、晶体结构、粒径、热稳定性和蓄热能力方面已被表征。Sn@Al2O3 纳米颗粒表现出最好的热行为，因为由于涂层的氧化屏障，它们在 100 次循环中的相变焓降低最低。此外，纳米颗粒和基于太阳能盐的纳米流体的比热增加，使纳米封装相变材料适用于热能储存应用。