Supporting Information

High Performance, Flexible, Poly(3,4-ethylenedioxythiophene) Supercapacitors

Achieved by Doping Redox Mediators in Organogel Electrolytes

Huanhuan Zhang, Jinyu Li, Cheng Gu, Mingming Yao, Bing Yang , Ping Lu and

Yuguang Ma*

1. Materials and methods

2. Calculations.

3. Photos of fabricated OGEs films

4. Diffusion coefficients of Fc and 4-oxo TEMPO in propylene carbonate

5. Characterizations of deposited PEDOT film

6. Determination of the operating voltage of supercapacitors

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Section 1:Materials and methods

Tetraethylammonium tetrafluoroborate (98%), was purchased from Alfa

Aesar. Before use, it was recrystallized from ethanol and dried for 24 h under

vacuum. Dichloromethane and acetonitrile were purified by distillation with CaH2

(50 g L-1) as the water removal agent. Super dry propylene carbonate was

purchased from J & K with water content < 5 ppm. Polymethylmethacrylate was

purchased from Alfa Aesar with Mw = 55000. Before use, it was kept in an oven

at 80 0C for desiccation. Carbon cloth was purchased from Taiwan CeTech,

model WOS1002. Before use, it was sonic cleaned with water, acetone, and

ethanol successively, each for 30 min and then dried. All the other chemical

reagents were used as received.

Electrochemical experiments were performed on a CHI 660 C

Electrochemical Workstation. The impendence measurement was performed

under open circuit potential in an AC frequency range from 100000 to 0.1 Hz

with the excitation signal of 5 mV. All the electrochemical tests were conducted

under N2 atmosphere in the glove box.

Ionic conductivity tests were conducted by sandwiching OGEs (0.02 cm

thick) between two stainless steel plates (1 cm2) to fabricate block cells.

Thermogravimetric analyses (TGA) under N2 atmosphere, with a heating rate

of 10 0C min-1.

The mass loading of PEDOT on carbon cloth was weighted by Mettler

Toledo XP6 ultramicro balance with 0.001 mg readability.

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Scanning electron microscope images were recorded on a JEOL model

FESEM-6700F at an accelerating voltage of 5 kV.

Fourier Transform Infrared (FTIR) spectra were recorded on a VERTEX

80V spectrometer with spectrum KBr as a reference.

X-ray diffraction diagram was recorded on a Rigaku SmartLab 3

diffractometer operated at 40 kV and 30 mA with filtered 0.15 nm Cu K

radiation.

Section 2: Calculations

1) Diffusion coefficient

Diffusion coefficients of Fc and 4-oxo TEMPO in GPE and propylene

carbonate were calculated according to the Randles–Sevcik equation:

i.e,

where is the peak value of anodic current in CV, is the number of

electrons transfered, 1, A is the area of the glassy carbon electrode, 0.07 cm2,

is the concentration of redox mediators, 50 mM, is the scan rate.

2) Specific capacitance

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Specific capacitance of PEDOT electrodes were calculated from the

discharging part of galvanostatic charge-discharge curve, according to the

formula:

where I is the discharging current, t is the time of discharging part, is the

open circuit voltage, m is the mass loading of one PEDOT electrode.

3) Power density and energy density

Where is the open circuit voltage, M is the mass of supercapacitor device,

the sum of two PEDOT electrodes, is the effective series resistance of

supercapacitor device, calculated from the IR drop of the galvanostatic charge-

discharge curve, is the capacitance of the whole device.

Section 3: Photos of fabricated OGEs films

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Figure S1. Photos of flexible and transparent OGE films, from left to right,

blank OGE, Fc doped OGE and 4-oxo TEMPO doped OGE.

Section 4: Diffusion coefficients of Fc and 4-oxo TEMPO in propylene

carbonate

Figure S2. Cyclic voltammograms of a) Fc and b) 4-oxo TEMPO in

propylene carbonate at scan rate 5 ,10, 20, 50, 100, 200, 400 mV s -1; c) peak

currents of Fc and 4-oxo TEMPO as a function of scan rates.

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Section 5: Characterizations of deposited PEDOT film.

Figure S3. Fourier Transform Infrared (FTIR) spectra of PEDOT film. The

sample was prepared by scratching PEDOT from carbon cloth and then

grinding them with KBr. Absorption peaks around 435, 555, 1307 and 1517

cm-1 are due to stretching of C=C in thiophene ring. Absorption peaks at

around 1068, 1194 cm-1 are originated from stretching of C-O-C bond in the

ethylene dioxy group. Vibrations of C-S bond in the thiophene ring are seen

in 683, 833, and 980 cm-1.[S1]

Figure S4. X-ray diffraction pattern of PEDOT film deposited on carbon

cloth.

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Section 6: Determination of the operating voltage of supercapacitors.

Figure S5. Cyclic voltammograms of PEDOT supercapacitor at the scan rate

of 50 mV s-1. When the potential is higher than 1.5 V, PEDOT is almost

redox inactive. So the voltage of supercapacitors is limited to 1.5 V.

Reference

[S1]Y.-K. Hsu, Y.-C. Chen, Y.-G. Lin, L.-C. Chen, K.-H. Chen, J. Power Sources 242 (2013) 718-724.

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