Palmitic acid/expanded graphite/CuS composite phase change materials toward efficient thermal storage and photothermal conversion

• Published in: Dalton transactions : an international journal of inorganic chemistry 2023-07, Vol.52 (28), p.9797-988
• Main Authors: Huo, Ying-Jie, Yan, Ting, Li, Zhi-Hui, Li, Shu-Yao, Pan, Wei-Guo
• Format: Article
• Language: English
• Subjects: Binding sites; Chemical synthesis; Copper sulfides; Energy storage; Energy utilization; Graphite; Heat conductivity; Heat transfer; Multilayers; Palmitic acid; Phase change materials; Photothermal conversion; Solar energy; Stability analysis; Storage capacity; Thermal conductivity; Thermal stability; Thermal storage
• ISSN: 1477-9226; 1477-9234
• DOI: 10.1039/d3dt01539d

In this study, an expanded graphite (EG) with nano-CuS (EG/CuS) support material with a special morphology was prepared, with EG/CuS filled with different ratios of palmitic acid (PA). Finally, a PA/EG/CuS composite phase change thermal storage material with photothermal conversion performance was synthesized. The superb chemical and thermal stability of PA/EG/CuS was demonstrated by characterization and analysis of the experiments. EG, a multi-layer structured material, provides rich binding sites for PA and nano-CuS and constructs rich thermal conductivity paths, which effectively improves the thermal conductivity of PA/EG/CuS. It is noted that the maximum thermal conductivity of PA/EG/CuS reached 0.372 W m −1 K −1 and the maximum phase change thermal storage capacity reached 260.4 kJ kg −1 , which proved the excellent thermal storage properties of PA/EG/CuS. In addition, PA/EG/CuS exhibits excellent photothermal conversion performance, and the experimental results demonstrated that the best photothermal conversion efficiency of PA/EG/CuS reached 81.4%. The PA/EG/CuS developed in this study provides a promising method for fabricating excellent conductive and low leakage composite phase change materials for solar energy utilization and energy storage. The maximum thermal conductivity of PA/EG/CuS is 0.372 W m −1 K −1 , the maximum phase change enthalpy is 247.2 kJ kg −1 , and the maximum photothermal conversion efficiency is 81.4%.