title: Photoresponsive Self-Assembly of Surface Active Ionic Liquid.
abstract: A novel photoresponsive surface active ionic liquid (SAIL) 1-(4-methyl azobenzene)-3-tetradecylimidazolium bromide ([C14mimAzo]Br) with azobenzene located in the headgroup was designed. Reversible vesicle formation and rupture can be finely controlled by photostimuli without any additives in the aqueous solution of the single-tailed ionic liquid. The photoisomerization of the azobenzene derivative was investigated by (1)H NMR and UV-vis spectroscopy. Density functional theory (DFT) calculations further demonstrate that trans-[C14mimAzo]Br has less negative interaction energy, which is beneficial to aggregate formation in water. The incorporation of trans-azobenzene group increases the hydrophobicity of the headgroup and reduces the electrostatic repulsion by delocalization of charge, which are beneficial to the formation of vesicles. However, the bend of cis-azobenzene makes the cis-isomers have no ability to accumulate tightly, which induces the rupture of vesicles. Our work paves a convenient way to achieve controlled topologies and self-assembly of single SAIL.
authors.affiliation: Key Laboratory of Colloid and Interface Chemistry, Shandong University, Ministry of Education , Jinan 250100, China.
authors.forename: Aoli
authors.initials: A
authors.lastname: Wu
authors.affiliation: Key Laboratory of Colloid and Interface Chemistry, Shandong University, Ministry of Education , Jinan 250100, China.
authors.forename: Fei
authors.initials: F
authors.lastname: Lu
authors.affiliation: Key Laboratory of Colloid and Interface Chemistry, Shandong University, Ministry of Education , Jinan 250100, China.
authors.forename: Panpan
authors.initials: P
authors.lastname: Sun
authors.affiliation: Key Laboratory of Colloid and Interface Chemistry, Shandong University, Ministry of Education , Jinan 250100, China.
authors.forename: Xinpei
authors.initials: X
authors.lastname: Gao
authors.affiliation: Key Laboratory of Coal Science and Technology of Ministry of Education and Shanxi Province, Taiyuan University of Technology , Taiyuan 030024, China.
authors.forename: Lijuan
authors.initials: L
authors.lastname: Shi
authors.affiliation: Key Laboratory of Colloid and Interface Chemistry, Shandong University, Ministry of Education , Jinan 250100, China.
authors.forename: Liqiang
authors.initials: L
authors.lastname: Zheng