光开关分子在不同有机相变材料中光控热能的适用性研究  

Study on the Applicability of Photoswitch Molecules to Photo-controlled Thermal Energy in Different Organic Phase Change Materials

作　　者：汪毅 施娟[1] 陈振乾[1,2] WANG Yi;SHI Juan;CHEN Zhenqian(School of Energy and Environment,Southeast University,Nanjing,210096,Jiangsu,China;Jiangsu Province Key Laboratory of Solar Energy Science and Technology,Nanjing 210096,Jiangsu,China)

机构地区：[1]东南大学能源与环境学院,南京210096 [2]江苏省太阳能技术重点实验室,南京210096

出　　处：《工程热物理学报》2024年第3期803-810,共8页Journal of Engineering Thermophysics

基　　金：国家自然科学基金(No.52076040)。

摘　　要：有机相变材料(PCMs)因其具有可逆性蓄放热特性、高能量密度、可选则的工作温度以及无相分离现象,在储能领域得到了广泛的研究和应用,但是无法实现能量的长效储存和可控热释放。偶氮苯分子作为一种光响应分子,可以通过分子结构的调控能够实现光控相变,同时储存光热和相变热。本文研究了2种不同接枝基团(AZO-A-14、AZO-O-14)的光开关分子在直链烷烃和脂肪酸相变材料中,以不同比例混合后的可控相变行为。结果显示,光开关分子更适用脂肪酸相变材料的相变温度控制,不同浓度情况均是如此。其原因在于脂肪酸分子极性较大,使得光开关分子在顺式的亚稳态状态下能更好的分散在其中,阻碍了其成核。另外,采用酯基接枝的光开关分子(AZO-A-14)自身的光控温差小于采用醚基接枝的光开关分子(AZO-O-14),而AZO-A-14掺杂于相变材料中形成的光控温差更大。进一步的,我们分别解耦了相变焓和光异构化焓。本研究为今后光控相变材料的改进、发展和应用提供了思路。Organic phase change materials(PCMs)have been widely studied and applied in the field of energy storage due to reversible heat storage and release characteristics,high energy den-sity,optional operating temperature and no phase separation phenomenon.However,PCMs can-not achieve long-term energy storage and controlled heat release.As a kind of photoresponsive molecule,azobenzene molecule can realize photo-controlled phase change by the regulation of molec-ular structure,and store both photo-heat and phase change heat.In this paper,the controllable phase change behavior of two kinds of photoswitch molecules(AZO-A-14,AZO-O-14)in straight chain alkane and fatty acid phase change materials was studied after mixing in different proportions.The results show that the photoswitch molecules are more suitable for the phase change tempera-ture control of fatty acid phase change materials with different concentrations.The reason is that the polarity of fatty acid molecules is high,in which the photoswitch molecules at cis-metastable state can be well dispersed,preventing from nucleation.In addition,the photo-controlled tem-perature difference of the ester group grafted photoswitch molecule(AZO-A-14)is smaller than that of the ether group grafted photoswitch molecule(AZO-O-14),and the photo-controlled tem-perature difference of AZO-A-14 doped in PCMs is larger.Furthermore,we decouple enthalpy of phase transition and enthalpy of isomerization separately.This study provides ideas for the improvement,development and application of optically controlled phase change materials in the future.

关 键 词：偶氮苯 光开关 相变材料 储能 

分 类 号：TK123[动力工程及工程热物理—工程热物理]