1. Effect on aluminum corrosion of LiBF4 addition into lithium imide electrolyte; a study using the EQCM
Seung-Wan Songa, Thomas J. Richardson a, Guorong V. Zhuang b, Thomas M. Devine a,c,∗, James W. Evans , Electrochimica Acta 49 (2004) 1483–1490
W`/z : molecular weight
F : Faraday¡¯s constant
¥ÄM : Mass change
¥ÄQ : Charge passed to the electrode
I : current
¥ÄM/¥ÄE : slope of the mass curve versus potential
¥ÄE/¥Ät : sweep rate which changes sign with sweep direction
Fig. 1. Cyclic voltammograms (a) and mass increase (b) at different cycle numbers of aluminum in 1M LiBF4/EC + DMC; sweep rate = 5 mV/s. Instantaneous mpe values are superimposed on the plot of mass increase vs. potential.
Fig. 2. Cyclic voltammograms (a) and mass increase (b) at different cycle numbers of aluminum in 1M LiTFSI/EC + DMC; sweep rate = 5 mV/s. Instantaneous mpe values are superimposed on the plot of mass increase vs. potential.
Fig. 3. Chronoamperometric diagram (a) and mass change (b) of aluminum in 1M LiTFSI/EC+DMC; open circuit voltage at 2.2V, standing at 5V between 0 and 5 s and 2V between 6 and 40 s. Instantaneous mpe values are superimposed on the plot of mass increase
vs. potential.
Fig. 4. Comparative plots of cyclic voltammograms (a) and the corresponding mass increase (b) for aluminum at the first cycle in 1M LiTFSI/EC + DMC (—), 0.8M LiTFSI + 0.2M LiBF4/EC + DMC (. . . ) and 0.5M LiTFSI+0.5M LiBF4/EC+DMC (- - -); sweep rate = 5 mV/s.
2. EQCM measurements of solvent transport during Li intercalation in V2O5 xerogel films
Eiichi Shouji 1, Daniel A. Buttry , Electrochimica Acta 45 (2000) 3757–3764
Fig. 1. Cyclic voltammograms (left) and EQCM frequency measurements (right) for spin coated V2O5 xerogel on EQCM gold electrode in AN solution containing 0.5 M LiClO4: scan rates are as shown. Curve (f) was done immediately following the sequence of scans (a)–(e).
Table 1. Observed and calculated frequency changes for Li intercalation into V2O5
Fig. 2. Plots of cathodic (open symbols) and total charges (filled symbols) vs. scan rate for the four films listed in Table 1, all at 5 mV:s (see text for details). Film thicknesses within a set decrease from top to bottom.
Fig. 3. Plots of () cathodic charge, as calculated from Dfobs and () experimental cathodic charge vs. DF (see text for details).
3. EQCM study of electrodeposited PbO2 : Investigation of the gel formation and discharge mechanisms
David Pecha,b, Thierry Broussec, Daniel Belangera, Daniel Guayb, Electrochimica Acta 54 (2009) 7382–7388
Fig. 1. Cyclic voltammogram and simultaneous mass measurements during the electrodeposition of PbO2 on a gold-coated quartz crystal. The electrolyte was 0.1M Pb(NO3)2 in 1M HNO3 solution and the sweep rate was 20mVs−1.
Fig. 6. (A) Variation of mass (dashed line) and current (full line) during the discharge of a 200gcm−2 electrodeposited -PbO2 thin film in 1.5M H2SO4 at a scan rate of 50mVs−1. (B) Variation of mass (m) with the charge (Q) calculated from the curves shown in (A).
Fig. 10. Relationship between the mass change (m) and the quantity of charge (Q) obtained from in the second reduction cycle of an electrodeposited PbO2 in 1.5M H2SO4 at 50mVs−1.
Fig. 11. Experimental molar mass difference determined at 50mVs−1 in 1.5M H2SO4.
4. Electrochemical study of nanometer Co3O4, Co, CoSb3 and Sb thin films toward lithium
V. Pralong*, J.-B. Leriche, B. Beaudoin, E. Naudin, M. Morcrette, J.-M. Tarascon
Solid State Ionics 166 (2004) 295–305
Fig. 10. Comparison between potential and corresponding mass of the electrode versus mole number during the first discharge of Co and Co3O4 thin films versus lithium in LiPF6 (1 M) EC-DMC.
Fig. 11. Potential and corresponding mass of the electrode versus mole number of a 0.1 mg Co thin film (5 Hz, 200 mJ, 4 cm, 10 1 mbar O2, 15 min) versus lithium in LiPF6 (1 M) EC-DMC, (10 Li+/h rate) on the second discharge.
Fig. 13. Potential and corresponding mass of the electrode versus mole number of a 0.4 mg CoSb3 thin film (5 Hz, 200 mJ, 4 cm, 10 6 mbar, 15 min) versus lithium in LiPF6 (1 M) EC-DMC, (10 Li+/h rate) on the first discharge.
Fig. 14. Potential and corresponding mass of the electrode versus mole number of a 0.1 mg Sb thin film (5 Hz, 200 mJ, 4 cm, 10 6 mbar, 15 min) versus lithium in LiPF6 (1 M) EC-DMC, (10 Li+/h rate) on the first discharge.
5. Solvent co-deposition during oxygen reduction on Au in DMSO LiPF6
W.R. Torres, A.Y. Tesio, E.J. Calvo , Electrochemistry Communications 49 (2014) 38–41
Equivalent to the Saurbrey equation that relates the resonant frequency
with the arealmass of deposit
Fig. 2. Chronoamperometry for the ORR on Au/quartz EQCM in O2 saturated 0.1 M LiPF6 DMSO electrolyte. ED = 2.55 V and simultaneous ¥Äm/A.
Fig. 3. Integrated mass to charge plot for chronoamperometry data in Fig. 2.
6. Electrochemical quartz crystal microbalance study on the oxygen reduction reaction in Li+ containing DMSO solution
Xiao Jie a, Kohei Uosaki , Journal of Electroanalytical Chemistry 716 (2014) 49–52
Fig. 1. Simultaneously obtained (a) current and (b) frequency change and corresponding mass change at the gold electrode as a function of potential in DMSO solutions when potential was swept by 20 mV/s. (c) Mass change as a function of integrated charge based on the results of (a) and (b). (- - -): Oxygen saturated
100 mM TBAPF6/DMSO solution, ( ): Ar saturated 100 mM LiPF6/DMSO solution, and (hhh): oxygen saturated 100 mM LiPF6/DMSO solution.
Fig. 2. Simultaneously obtained (a) current and (b) frequency/mass change at the gold electrode in an oxygen saturated DMSO solution containing 100 mM LiPF6 as a function of time when the potential was first swept from 3.4 V to 2.73 V by 20 mV/s and then held at 2.73 V for 5 min ( ) and the potential was stepped from 3.4 V to 2.73 V and then held at 2.73 V for 20 min (- - -). (c) Mass change as a function of integrated charge based on the results of (a) and (b). Potential variations with time\ are shown as inset in (a).
Fig. 3. Simultaneously obtained (a) current and (b) frequency/mass change at the gold electrode in an oxygen saturated DMSO solution containing 100 mM LiPF6 as a function of time when the potential was first swept from 3.4 V to 2.55 V by 20 mV/s and then held at 2.55 V for 2 min ( ) and the potential was stepped from 3.4 V to
2.55 V and then held at 2.55 V for 20 min (- - -). (c) Mass change as a function of integrated charge based on the results of (a) and (b). Potential variations with time are shown as inset in (a).
7. Towards TiO2-conducting polymer hybrid materials for lithium ion batteries
Pawe©© Marek Dziewon¢¥ ski, Maria Grzeszczuk , Electrochimica Acta 55 (2010) 3336–3347
On the other hand, m is related to the electric charge Q by the Faraday¡¯s law,
so the total charge used for the electrode reactions passed at time t,
Qt , corresponding to the monitored frequency ft
Fig. 1. Dc currents (solid lines) and corresponding changes in the effective molar mass (light green lines) recorded during CV at 5mVs−1 for: (a) Ppy(TOS) (h = 0.56m) (see No. 5 in Table 1) and (b) PEDOT(TFSI) (see No. 6 in Table 1) in 1M LiClO4-PC; E vs. Ag/Ag+.
Fig. A1. CV-curves (25mVs−1) (a) and related −f response of a AuEQCM electrode (b) during an electropolymerization process of PPy(TOS); bathing solution: 0.1M Py in 0.05M TBAT-PC; see Table 1, 5th row; inset: linear dependence of the deposit mass (evaluated on the basis of measured electropolymerization charge and experimentally obtained value (x = 0.31) of the oxidation level of PPy(TOS)) on overall frequency changes.
Fig. A2. Analysis of the 1st voltammetric scans collected during electropolymerization process of the film ped4 (PEDOT(TFSI)) (a) and tpy1 (Ppy(TOS)) (b); the abscissa axes: total electropolymerization charge; more information about the samples: Table 1, 5 and 6th row; the arrows indicate the beginning of anion expelling; In the case of Ppy(TOS), two curves: Meff (obtained from analysis of row CV and EQCM-data using Eq. (3)) and Meff (theoretical) (calculated with assumption, that oxidation level (x) is approaching the value of 0.25) are more overlapped than in the case of PEDOT(TFSI). It suggests that PEDOT(TFSI) films are more viscoelastic than Ppy(TOS) films.
Fig. A3. Stability testing (voltammetric cycling: 5mVs−1, 50 scans) performed in 1.0MLiClO4-PC for a PEDOT(ClO4−) layer after its multiple electrochemical switching in the potential window (−1.5 V, 0.5 V): I–E and −f–E curves (a) and related Meff–E curves (b); the sample of PEDOT(ClO4 −) was prepared in the similar way as the PEDOT(TFSI) films. However PEDOT(ClO4−) films were more viscoelastic than similar PEDOT(TFSI) films.
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