阴离子-基质分子间作用调控增强PEO基离子凝胶热电性能  

Enhancing thermoelectric properties of PEO based ionic gel by regulation of anion-matrix intermolecular interaction

作　　者：张睿涵 王连军[1,2] 江莞[1,2,3] 孙婷婷[4] ZHANG Ruihan;WANG Lianjun;JIANG Wan;SUN Tingting(College of Materials Science and Engineering,Donghua University,Shanghai,China;State Key Laboratory for Modification of Chemical Fibers and Polymer Materials,Donghua University,Shanghai,China;Institute of Functional Materials,Donghua University,Shanghai,China;College of Biological Science and Medical Engineering,Donghua University,Shanghai,China)

机构地区：[1]东华大学材料科学与工程学院,上海 [2]东华大学纤维材料改性国家重点实验室,上海 [3]东华大学功能材料研究中心,上海 [4]东华大学生物与医学工程学院,上海

出　　处：《东华大学学报(自然科学版)》2025年第1期31-37,共7页Journal of Donghua University(Natural Science)

基　　金：国家自然科学基金(U23A20685);上海市教委科研创新项目(2021-01-07-00-03-E00110)。

摘　　要：离子热电材料因其毫伏级高热电势,在热电能源转换领域展现出巨大应用前景。基于分子间相互作用,调控实现其热电势的有效增强是离子热电材料的研究热点和难点。以1-乙基-3-甲基咪唑氯(EMImCl)和1-乙基-3-甲基咪唑-双三氟甲基磺酰亚胺(EMImTFSI)两类离子液体以及聚环氧乙烷(PEO)为原料制备离子凝胶,研究离子液体与聚合物基质的分子间相互作用差异及其对热电性能的影响,并通过阴离子组分调控,实现热电性能的有效提升。研究结果表明,EMImTFSI通过阴离子TFSI^(-)中的CF_(3)与PEO的—OH和CH_(2)产生氢键作用,EMImCl则通过阴离子Cl^(-)与PEO的—OH产生分子间氢键作用,且Cl^(-)与PEO的—OH之间的分子间氢键作用强于TFSI^(-),使得PEO基底聚合物不定形区域增加,有助于EMImCl在PEO基底获得更高的阴阳离子迁移差。最终,通过上述阴离子与基质分子间相互作用调控,PEO/EMImCl热电势相比PEO/EMImTFSI提高了约38%,其值可达12.51 mV/K,这为制备高性能离子热电材料提供更多可借鉴途径。Ionic thermoelectric materials show great application prospects in the field of thermoelectric energy conversion due to their millivolt-level high thermoelectric potential,and the research hotspots and difficulties in the field of ionic thermoelectric materials focus on effectively enhancing Seebeck coefficients by modulating intermolecular interactions.Two types of ionic liquids,1-ethyl-3-methylimidazolium chloride(EMImCl)and 1-ethyl-3-methylimidazolium bis(trifluoromethyl)sulfonimide(EMImTFSI),and poly(ethylene oxide)(PEO)are used as raw materials to prepare ionic gels,and the differences in intermolecular interactions between ionic liquids and polymer matrices and their effects on the thermoelectric properties are investigated to realize the effective enhancement of thermoelectric properties through the anionic component modulation.The results show that EMImTFSI generates hydrogen bonding interactions with—OH and CH_(2)of PEO through CF_(3)in the anion TFSI^(-),while EMImCl generates intermolecular hydrogen bonding interactions with—OH of PEO through the anion Cl^(-),and the intermolecular hydrogen bonding interactions between Cl^(-)and—OH of PEO are stronger than those of TFSI^(-),resulting in the increase of polymer indeterminate regions in the PEO substrate.It helps EMImCl to obtain higher anion mobility difference in PEO substrate.Finally,through the modulation of the anion-substrate intermolecular interactions mentioned above,the Seebeck coefficient of PEO/EMImCl is increased by 38%compared with that of PEO/EMImTFSI,and its value can reach 12.51 mV/K,which provides more referable pathways for the preparation of highperformance ionic thermoelectric materials.

关 键 词：离子热电 分子间相互作用 热电势 离子液体 

分 类 号：TB34[一般工业技术—材料科学与工程]