Li + Solvation in Glyme-Li Salt Solvate Ionic Liquids

Transcription

1 Eletroni Supplementary Material (ESI) for Physial Chemistry Chemial Physis. This journal is the Owner Soieties 15 Supplementary Information: + Solvation in Glyme- Salt Solvate Ioni quids Kazuhide Ueno, a Ryoihi Tatara, a Seiji Tsuzuki, b Sohi Saito, Hiroyuki Doi, Kazuki Yoshida, a Toshihiko Mandai, a Masaru Matsugami, d Yasuhiro Umebayashi, Kaoru Dokko, a Masayoshi Watanabe* a a Department of Chemistry and Biotehnology, Yokohama National University,79-5 Tokiwadai, Hodogaya-ku, Yokohama 4-851, Japan b Researh Initiative of Computational Sienes (RICS), Nanosystem Researh Institute, National Institute of Advaned Industrial Siene and Tehno logy (AIST), Umezono, Tsukuba, Ibaraki , Japan Graduate Shool of Siene and Tehnology, Niigata University, 85 Ikarashi, -no-ho, Nishi-ku, Niigata City, , Japan d aulty of beral Studies, Kumamoto National College of Tehnology, 659- Suya, Koshi, Kumamoto , Japan AUTHOR ADDRESS:mwatanab@ynu.a.jp 1

2 igure S1. Typial results on the deonvolutions of Raman spetra into four bands at around 81, 835, 85, and 873 m 1, by the Gaussian-Lorentzian funtion. igure S. Normalized Raman spetra of (a) G3-[TSA] mixtures, (b) G3-[OTf] mixtures, () G4-[BETI] mixtures, (d) G4-[TSA] mixtures, (e) G4-ClO 4 mixtures, and (f) [(G4) 1]X.

3 igure S3. Ioni ondutivity plotted against salt onentration in the G3-[TSA] and the G3-[OTf] mixtures at 3 C. Eletrode potentials of / +. The eletrode potential E was alulated by the following proedure, with f values obtained from Raman spetrosopi analysis (Table S1). Table S1. Estimated value of onentration of free G3 in [(G3) n][tsa] at 3 C by Raman study. f (mol%) f (mol dm 3 ) [(G3) 1 ][TSA].3.71 [(G3) 1. ][TSA] [(G3) 1.5 ][TSA].78 [(G3) ][TSA] [(G3) 4 ][TSA] The potential E of the referene eletrode, / + in 1 mol dm 3 [TSA]/G3 (=[(G3)4.8][TSA]) an be written as: 1 E ' E log 3.8 E E ' log 3.8 (S1) Substituting Eq. S1 in Eq. 7, we get: 3

4 E a (S) a E ' log 3.8 log where E is, beause it represents the referene eletrode potential. Thus, we an alulate E by substituting a+ = and a = G in the dilute solutions ( 1mol dm 3 for G3-[TSA] mixtures), and a+ =, a = f in the onentrated regime (> 1mol dm 3 ) in igure 9. Although we assume a+ (= a+ )= for the sake of simpliity, the ativities an indeed be represented as a+ (= a+ ) = γ with the ativity oeffiient of + (γ). If the ativity oeffiient is taken into onsideration, the Nernst equation of the eletrode reation; + + e, an be modified as: E1 E1 loga E1 log log (S3) The eletrode potential (E 1 ) in the referene solution of = 1 mol dm 3 with the ativity oeffiient (γ, 1M) an be written as: E1 ' E1 log,1m( ) E1 E1 ' log,1m (S4). Substituting Eq. S4 in Eq. S3, we obtain: E 1 E1 ' log log,1m (S5) In Eq. S5, the first term (E 1 ) is beause / + in 1 mol dm 3 [TSA]/G3 is the referene eletrode, the seond term represents the error aused by the variation of ativity oeffiient with + onentration, and the third term is a alulable value. Thus, the differene between experimental and alulated values of the eletrode potential originated from the seond term. igure S4 indiates that the 4

5 ativity oeffiient (γ) was a little higher than that of the 1 mol dm 3 in the lower onentration region (< 1 mol dm 3 ). In the highly onentrated regime, the drasti inrease in the eletrode potential an also be desribed by the seond term with the ativity oeffiients in Eq. S5. In the ase of [(G3)][TSA], for example, the experimental data for / + eletrode potential is.3 V, whereas the alulated value is.9 V based on Eq. 6, E = log / (igure S4). If the interpretation of the differene between the experimental and alulated values (.1 V) was imposed to the seond term in Eq. S5, γ must be 176 times higher than γ, 1M. However, physial meaning of the signifiantly high γ is obsure. Instead, we attempted to explain the drasti potential hange by onsidering the ativity of the free s without imposing the ompensation of the ativity oeffiients. igure S4. Plots of the experimental and alulated (based on Nernst Equation) value of / + eletrode potential against ommon logarithm of the salt onentration in [(G3) n ][TSA] at 3 C. Referene eletrode was / + in 1 mol dm -3 [TSA]/G3. or the modified eletrode reation aompanied by de-solvation proess, + + e +, Nernst equation with the ativity oeffiients of + (γ+) and (γ) an be modified as follows: 5

6 E E E a log a log log f (S6) The eletrode potentials (E ) in the referene solution with [(G3)1] + = 1 mol dm 3, and = 3.8 mol dm 3 are; E E ' E log [(G3)],1M G3free,3.8M E ' log [(G3)],1M G3free,3.8M log 3.8( ) log 3.8 (S7) Substituting Eq. S7 in Eq. S6, we obtain: E G3free,3.8M E ' log log log3.8 log [(G3)],1M f (S8) In Eq. S8, the first term is beause / + in 1 mol dm -3 [TSA]/G3 is referene eletrode, the seond and third terms represent the error aused by the hange in the ativity oeffiients of the omplex ation and the free s against + onentration, the fourth term is onstant, and the fifth term is a alulable value. The drasti inrease in the potential at high onentrations an be explained by the fifth term as G3free in the denominator. However, the differene between experimental and alulated values in igure 9 ould originate from the seond and third terms, as well as Eq. S5. 6