1. Controlled morphology of
electrodeposited CuSCN by
variation of applied bias
voltage
Presented by
SOHAM GHOSH
Dept. Energy Science and Engineering
ICAER-2013

2. Outline
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Sensitized solar cell (SSC),
Motivation of the work,
Applied bias dependent CuSCN morphology,
Deposition time dependent CuSCN morphology,
Application,
Summary.
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3. Dye Sensitized Solar Cell
 Contains three individual layers
namely: the electron collector, absorber
layer or the dye and the electrolyte or
hole conducting material
 e-h pairs separated due the presence
of band-offset at each interface
Efficiency reached > 11% for lab based
devices
Easy fabrication; Less energy
consuming
Less pay-back period than Si based solar cell
DSSC
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4. Semiconductor Sensitized Solar Cell
Degradation of dye with time (mainly the UV degradation)
Liquid electrolyte (improper packaging)
FTO
Au
•Dye is replaced by a low band-gap semiconductor
material leading to an intermediate solid state
DSSC,
•Electrolyte is
also replaced by a solid
semiconductor making the whole device as a solid
state device.
CuSCN
CdS
ZnO
Electron
Hole
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5. Motivation of the work
CuSCN
Sensitizer
ZnO Nanorods
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6. Contd.
Ag
Electron
Collector
Sensitizer
CuSCN
Nanorod
FTO
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7. Contd.
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The percolation of hole collecting material into the pores in nanoporous
substrates is quite limited,
Inverse structural design using p-type semiconductor nanorods as
building blocks,
Surface area will increase and interface charge recombination will
reduce resulting better charge transport,
Hole conducting pathway that is likely to be diffusion limited in
comparison to the hoping and grain boundary dominated transport
mechanism.
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8. Applied Bias Dependent CuSCN Morphology
SEM images of the CuSCN films deposited at (A) -0.30 V, (B) -0.31 V, (C) 0.32 V, (D) -0.35 V, (E) -0.40 V (F) -0.42 V
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9. XRD Pattern of CuSCN
* FTO Glass
*
* *
Intensity (a.u.)
*
10
15
20
25
30
35
40
*
*
60
65
*
(107)
(113)
(241)
(006)
(104)
(015)
(101)
(003)
*
*
-0.30V
-0.31V
-0.32V
-0.35V
-0.40V
-0.42V
45
50
55
70
75
80
2 Theta (deg.)
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10. Deposition Time Dependent CuSCN Morphology
SEM of time dependant deposition film for (A) 1hr (B) 2hr (C) 3hr
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11. TEM of CuSCN Nanorods
Transmission electron microscopy of CuSCN nanorods
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12. Photovoltaic Application
Jsc = 8.8 mA/cm2
Voc = 0.68
FF = 0.63
η = 3.9%
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13. Summary
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Well shaped nanorods can be deposited under a potential of -0.3V,
With increasing the applied potential nanorods were started
agglomerated gradually,
With increasing deposition time the nanorods diameter started to
increase,
Application for Semiconductor Sensitized Solar Cell.
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15. Fabrication Methodology of Copper Thiocyanate
Experimental details:
• Electrolyte contains Cu+2 and SCN- ions in a water-ethanol system
Applied Potential: -0.3 to -0.42 V
Reaction at Cathode:
• Cu(ClO4)2
• NaSCN
• Cu+2 + SCN• CuSCN+ + e-
Cu2+ + 2ClO4Na+ + SCNCuSCN+
CuSCN
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16. SEM images of the CuSCN films deposited at (A) -0.30 V, (B) -0.31 V
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17. SEM images of the CuSCN films deposited at (C) -0.32 V, (D) -0.35 V
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18. SEM images of the CuSCN films deposited at (A) -0.40 V, (B) -0.41 V
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