5 Polymer Solar Cells: Development of π-Conjugated Polymers …
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Table 5.1 Backbone orientation, charge carrier mobility, and photovoltaic parameters of polymerbased BHJ cells for PTzBT-12HD, -12OD, -14HD, -14OD, -EHOD, and -BOHD
Side
chains
Orientation a
Photovoltaic parameters
p:n
ratio b
Thickness
[nm]
J SC [mA/cm 2 ]
V OC [V]
FF
PCE
[%]
12HD
Bimodal
1:2
130
7.8
0.81
0.67
4.2
200
10.0
0.81
0.60
4.8
270
10.7
0.81
0.53
4.4
350
11.8
0.80
0.41
3.8
12OD
Face-on
1:2
130
8.9
0.83
0.66
4.9
210
10.7
0.82
0.62
5.5
260
11.3
0.82
0.62
5.8
370
11.5
0.82
0.61
5.7
14HD
Edge-on
1:2
110
8.4
0.81
0.67
4.5
200
9.9
0.82
0.66
5.4
270
11.3
0.81
0.55
5.0
360
11.7
0.78
0.52
4.8
14OD
Bimodal
1:2
120
8.9
0.82
0.67
4.9
190
9.8
0.82
0.64
5.1
260
10.9
0.81
0.54
4.8
370
10.8
0.79
0.53
4.5
EHOD
Edge-on
1:2
120
8.5
0.89
0.68
5.2
190
10.3
0.88
0.64
5.8
260
11.1
0.87
0.56
5.4
380
11.3
0.88
0.52
5.1
BOHD
Face-on
1:2
120
8.9
0.91
0.68
5.5
200
10.1
0.90
0.67
6.1
270
11.4
0.89
0.65
6.7
400
11.8
0.89
0.62
6.5
540
12.2
0.88
0.60
6.4
810
12.8
0.87
0.53
5.9
1020
12.9
0.87
0.51
5.8
1:2 c
330
12.7
0.90
0.65
7.5
a Backbone orientation in the polymer-only film. b Polymer (p) to PCBM (n) weight ratio. c PC 71 BM
was used as the n-type material