ITP OpenIR  > SCI期刊论文
Li, Shen1; Safari, Niloufar2; Saielli, Giacomo2,3; Wang, Yanting1
Liquid-Liquid Phase Separation of Viologen Bistriflimide/Benzene Mixtures: Role of the Dual Ionic and Organic Nature of Ionic Liquids
AbstractLiquid-liquid phase separation occurs at room temperature when mixing an excess of benzene with solid viologen bistriflimide salts with various alkyl side-chain lengths. A liquid phase composed of (almost) pure benzene is above the other sponge-like liquid phase with salt absorbed in benzene. Nuclear magnetic resonance experiments indicate that the mole ratio of benzene/salt in the sponge-like phase remains unchanged upon varying the amounts of (nonexcessive) salt or benzene. Moreover, the benzene/viologen salt mole ratio in the sponge-like phase increases linearly with respect to the side-chain length of the cation. Similarly, when an excess of viologen salt is added in benzene, a sponge-like liquid phase composed of salt absorbed by benzene is observed in equilibrium with some solid viologen salt neither dissolved nor absorbed by the solvent. The mole ratio of the sponge-like liquid phase again increases linearly with side-chain length, while it remains independent of the relative amount of benzene and viologen salt as long as the latter is in excess. Finally, when appropriate amounts of benzene and viologen salt are mixed, a single sponge-like liquid phase is observed at an intermediate composition between the lower and upper limits. Molecular dynamics simulations reveal that because of their dual ionic and organic nature, when absorbed in benzene, the studied salts form nanoscale segregated liquid structures, akin ionic liquids, with a continuous polar network composed of anions and cationic charged groups, along with nonpolar domains composed of alkyl cationic side chains. Benzene molecules are preferentially absorbed inside the nonpolar region, which effectively expands the nonpolar region to be sponge-like and consequently liquidizes the viologen salt. The linearity of the benzene/salt ratio in the upper and lower phase boundaries comes from the fact that the effective volume of the nonpolar region for accommodating benzene molecules grows linearly with cationic alkyl side-chain length. The occurrence of the above phenomena is attributed to the nonpolar feature of benzene molecules, and there is no evidence of pi-pi or ion-pi interaction between the ions and benzene molecules. Moreover, the diffusion of benzene in the sponge-like phase is found to be close to that in n-alkanes, supporting the idea of nanoscale segregation of polar and nonpolar regions in the sponge-like phase. The revealed mechanism is anticipated to be general for understanding liquid-liquid phase separation observed in mixtures of organic salts (ionic liquids) having relatively long alkyl chains with small organic molecules.
Cooperation Status国际
Subject AreaChemistry
MOST Discipline CatalogueChemistry, Physical
Indexed BySCIE
Citation statistics
Document Type期刊论文
Affiliation1.Chinese Acad Sci, Inst Theoret Phys, CAS Key Lab Theoret Phys, Beijing 100190, Peoples R China
2.Univ Chinese Acad Sci, Sch Phys Sci, Beijing 100049, Peoples R China
3.Univ Padua, Dept Chem Sci, I-35131 Padua, Italy
4.CNR Inst Membrane Technol, Unit Padova, I-35131 Padua, Italy
Recommended Citation
GB/T 7714
Li, Shen,Safari, Niloufar,Saielli, Giacomo,et al. Liquid-Liquid Phase Separation of Viologen Bistriflimide/Benzene Mixtures: Role of the Dual Ionic and Organic Nature of Ionic Liquids[J]. JOURNAL OF PHYSICAL CHEMISTRY B,2020,124(36):7929-7937.
APA Li, Shen,Safari, Niloufar,Saielli, Giacomo,&Wang, Yanting.(2020).Liquid-Liquid Phase Separation of Viologen Bistriflimide/Benzene Mixtures: Role of the Dual Ionic and Organic Nature of Ionic Liquids.JOURNAL OF PHYSICAL CHEMISTRY B,124(36),7929-7937.
MLA Li, Shen,et al."Liquid-Liquid Phase Separation of Viologen Bistriflimide/Benzene Mixtures: Role of the Dual Ionic and Organic Nature of Ionic Liquids".JOURNAL OF PHYSICAL CHEMISTRY B 124.36(2020):7929-7937.
Files in This Item:
File Name/Size DocType Version Access License
Liquid-Liquid Phase (5303KB)期刊论文出版稿开放获取CC BY-NC-SAApplication Full Text
Related Services
Recommend this item
Usage statistics
Export to Endnote
Google Scholar
Similar articles in Google Scholar
[Li, Shen]'s Articles
[Safari, Niloufar]'s Articles
[Saielli, Giacomo]'s Articles
Baidu academic
Similar articles in Baidu academic
[Li, Shen]'s Articles
[Safari, Niloufar]'s Articles
[Saielli, Giacomo]'s Articles
Bing Scholar
Similar articles in Bing Scholar
[Li, Shen]'s Articles
[Safari, Niloufar]'s Articles
[Saielli, Giacomo]'s Articles
Terms of Use
No data!
Social Bookmark/Share
All comments (0)
No comment.

Items in the repository are protected by copyright, with all rights reserved, unless otherwise indicated.