When nano-fillers are used to enhance the thermal conductivity of organic phase change materials(PCMs),the naturally formed interface is considered to hinder thermal transport of the composite PCMs.However,the effect ...When nano-fillers are used to enhance the thermal conductivity of organic phase change materials(PCMs),the naturally formed interface is considered to hinder thermal transport of the composite PCMs.However,the effect of the interface on the thermal properties of surrounding PCM has not been fully studied.In this paper,three composite PCMs(Ery@SiC,Ery@SiO_(2) and Ery@Si_(3)N_(4))were prepared by melt-blending method.The local thermal conductivity and reduced Young’s modulus(E^(*))of the erythritol at the interface and far away from the interface in the composite PCMs were simultaneously measured by scanning thermal microscopy(SThM).The results revealed significant enhancement in local thermal conductivity of erythritol at the interface and its obvious positive correlation with E^(*).For different composite PCMs,molecular dynamics(MD)simulations suggested that the increase in intrinsic thermal conductivity and E^(*)of erythritol is attributed to the increase in interaction energy between erythritol and nanoparticles,as more erythritol phonon vibrations transform from localized mode to delocalized mode and erythritol has a higher density at the interface.These findings will provide new ideas for the design of PCM for energy storage.展开更多
基金supported by the National Key R&D Program of China(No.2023YFF0612804)the National Natural Science Foundation of China(Nos.52222602,52236006,and 22293043)+3 种基金Beijing Nova Program(No.20220484170)the Fundamental Research Funds for the Central Universities(Nos.FRF-TP-22-001C1 and FRF-EYIT-23-05)Foundation of the Youth Innovation Promotion Association of CAS(No.2020048)IPE Project for Frontier Basic Research(No.QYJC-2023-08).
文摘When nano-fillers are used to enhance the thermal conductivity of organic phase change materials(PCMs),the naturally formed interface is considered to hinder thermal transport of the composite PCMs.However,the effect of the interface on the thermal properties of surrounding PCM has not been fully studied.In this paper,three composite PCMs(Ery@SiC,Ery@SiO_(2) and Ery@Si_(3)N_(4))were prepared by melt-blending method.The local thermal conductivity and reduced Young’s modulus(E^(*))of the erythritol at the interface and far away from the interface in the composite PCMs were simultaneously measured by scanning thermal microscopy(SThM).The results revealed significant enhancement in local thermal conductivity of erythritol at the interface and its obvious positive correlation with E^(*).For different composite PCMs,molecular dynamics(MD)simulations suggested that the increase in intrinsic thermal conductivity and E^(*)of erythritol is attributed to the increase in interaction energy between erythritol and nanoparticles,as more erythritol phonon vibrations transform from localized mode to delocalized mode and erythritol has a higher density at the interface.These findings will provide new ideas for the design of PCM for energy storage.
