摘要
本文制备了两种管径、不同填充率的碳纳米管填充十二酸的定形相变材料,对其结构和相变特性进行表征。结果表明,十二酸填充到碳管中后熔点和潜热降低,同时随着填充率的减小,熔点和潜热继续降低,当填充率减小到15.5%时,不再发生相变。分子动力学模拟所得结果与实验一致,同时微观结构分析表明,十二酸分子在碳管内优先附壁形成非晶相,而相变特性取决于碳管中心的晶相结构。进一步基于Gibbs-Thomson方程,可以获得复合材料熔点降低值与结构参数的线性关系。
Two kinds of CNTs with different inner diameters were successfully filled with different ratios of LA and their structures and phase change properties were characterized. The results showed that the melting point and latent heat of LA confined in carbon nanotubes were lower than those of the bulk material, and both decrease as the diameters of CNTs and the filling ratios of LA decrease.Molecular dynamics(MD) simulations indicated that the LA molecules form a liquid layer near the pore walls and crystallize in the pore center. When the LA’s filling ratio was reduced to a certain value, all LA molecules are attached to the inner walls of CNTs, hindering their crystallization. A linear relationship between melting temperature shift and structural properties was obtained based on the modified Gibbs-Thomson equation, which gives an insight into the relationship between phase change properties and microstructures.
作者
魏润枝
冯妍卉
黄志
张欣欣
WEI Run-Zhi;FENG Yan-Hui;HUANG Zhi;ZHANG Xin-Xin(School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China;Beijing Key Laboratory of Energy Saving and Emission Reduction for Metallurgical Industry, University of Science and Technology Beijing, Beijing 100083, China;Metallurgical and Chemical Industry Department, China ENF I Engineering Corporation, Beijing 100038, China)
出处
《工程热物理学报》
EI
CAS
CSCD
北大核心
2019年第6期1362-1368,共7页
Journal of Engineering Thermophysics
基金
国家自然科学基金资助项目(No.51706016,No.51422601)
关键词
碳纳米管
十二酸
定形相变材料
carbon nanotubes
lauric acid
shape-stabilized phase change material
