Supporting Information

Novel fluoride-substituted donor/acceptor polymers containing benzodithiophene and quinoxaline units for use in low–band gap solar cells

Ashutosh Singh, Ravinder Singh, Chein-Min Lin, Murali Krishna Pola, Chiao-Kai Chang, Kung-Hwa Wei*, Hong-Cheu Lin*

Department of Materials Science and Engineering, National Chiao Tung University, Hsinchu, Taiwan 300.

1. Fig. S1 --------------------------------------------------------------------------------------------------------------------------- page S2

2. Fig S2 ---------------------------------------------------------------------------------------------------------------------------- page S3

3. Fig S3 ---------------------------------------------------------------------------------------------------------------------------- page S4

4. Fig S4 ---------------------------------------------------------------------------------------------------------------------------- page S5

5. Fig S4 ---------------------------------------------------------------------------------------------------------------------------- page S6

6. Table S1 ------------------------------------------------------------------------------------------------------------------------- page S7

7. Table S2 ------------------------------------------------------------------------------------------------------------------------- page S8

8. Table S3 ------------------------------------------------------------------------------------------------------------------------- page S9

9. Table S4 ------------------------------------------------------------------------------------------------------------------------- page S10

10. Fig S5 --------------------------------------------------------------------------------------------------------------------------- page S11

11. 1H-NMR data of intermediate 5 --------------------------------------------------------------------------------------------- page S12

12. 1H-NMR data of intermediate AM1 ---------------------------------------------------------------------------------------- page S13

13. 13C-NMR data of intermediate AM1 --------------------------------------------------------------------------------------- page S14

14. 1H-NMR data of intermediate AM2 ---------------------------------------------------------------------------------------- page S15

15. 1H-NMR data of intermediate AM2 ---------------------------------------------------------------------------------------- page S16

16, 1H-NMR data of polymers------------------------------------------------------------------------------------------------------page S17-20

17. Elementary analysis mass data of AM1 and AM2 ------------------------------------------------------------------------ page S21

18. Elementary analysis mass data of DM1 and DM2 ------------------------------------------------------------------------ page S22

19. Elementary analysis mass data of PTF1, POF1, PTF2, and POF2 ---------------------------------------------------- page S23

S1

Fig. S1. Basic device structure of the polymer solar cells.

S2

Fig. S2. FTIR spectra of polymers PTF1, POF1, PTF2, and POF2.

S3

Fig. S3. XRD data of polymers PTF1, POF1, PTF2, and POF2.

S4

Fig. S4. TGA and their corresponding thermogravimetric derivative (DTG) data of polymers (a) PTF1, (b) POF1, (c) PTF2, and (d) POF2 at a heating rate of 20 °C/min.

S5

Fig. S5. DSC data of polymers PTF1, POF1, PTF2, and POF2 at a heating rate of 10 °C/min.

S6

Table S1 Performances of photovoltaic devices incorporating the polymer PTF1 blended with PC60BM or PC70BM.

PTF1:PC60BM/ PC70BM

RPM/ Concentrationa

[mg mL–1]

Anneal [°C]

Voc [V] Jsc [mA cm–2] FF PCE [%]

PTF1:PC60BM

1:1 in CB 1000/3 X 0.76 2.23 0.25 0.43

1600/3 X 0.54 2.71 0.26 0.39

2400/3 X 0.75 1.36 0.26 0.22

1600/3 90 0.66 2.95 0.3 0.51

2400/4 X 0.68 0.75 0.23 0.12

3200/4 X 0.67 0.1 0.23 0.12

4200/4 X 0.68 0.57 0.25 0.09

1:1.5 in CB 1800/3 X 0.63 2.53 0.30 0.47

800/3 120 0.65 2.03 0.32 0.43

1300/3 120 0.56 2.24 0.29 0.37

1800/3 120 0.57 2.95 0.30 0.51

PTF1:PC70BM

1:1 in CB 1200/3 X 0.75 3.18 0.31 0.74

800/3 120 0.71 2.72 0.32 0.64

1200/3 120 0.69 2.80 0.30 0.58

1800/3 120 0.72 4.97 0.29 1.04

1.5:1 in CB 1000/3 X 0.71 1.59 0.25 0.25

1600/3 X 0.72 1.38 0.21 0.21

2400/3 X 0.53 1.90 0.25 0.26

1600/3 120 0.74 2.07 0.25 0.38

2400/3 120 0.71 2.53 .025 0.45

aTotal concentration of the polymer:PC60BM/PC70BM in solution.

S7

Table S2 Performances of photovoltaic devices incorporating the polymer POF1 blended with PC60BM or PC70BM.

POF1:PC60BM/ PC70BM

RPM/ Concentrationa

[mg mL–1]

Anneal [°C]

Voc [V] Jsc [mA cm–2] FF PCE [%]

POF1:PC60BM1:1 in CB 800/3 X 0.73 0.60 0.26 0.11

1200/3 X 0.72 0.92 0.25 0.171600/3 X 0.70 1.10 0.24 0.192000/3 X 0.75 1.44 0.25 0.27800/3 X 0.72 1.09 0.23 0.181200/3 X 0.76 1.42 0.24 0.261600/3 X 0.77 2.01 0.24 0.372000/3 X 0.74 2.27 0.26 0.44

1:2 in CB 800/3 X 0.70 2.85 0.26 0.521200/3 X 0.66 2.49 0.29 0.47

1600/3 X 0.73 2.08 0.27 0.412000/3 X 0.58 2.11 0.29 0.36

POF1:PC70BM1:1.5 in CHCl3 1500/3 X 0.72 3.11 0.27 0.61

2000/3 X 0.78 4.42 0.30 1.032500/3 X 0.79 5.17 0.30 1.222000/3 1% DIO 0.75 2.8 0.30 0.632500/3 1% DIO 0.73 1.46 0.27 0.27

aTotal concentration of the polymer:PC60BM/PC70BM in solution.

S8

Table S3 Performances of photovoltaic devices incorporating the polymer PTF2 blended with PC60BM or PC70BM.

PTF2:PC60BM/ PC70BM

RPM/ Concentrationa

[mg mL–1]

Anneal [°C]

Voc [V] Jsc [mA cm–2] FF PCE [%]

PTF2:PC60BM1:1 in CB 1000/3 X 0.79 3.19 0.33 0.84

1600/3 X 0.59 3.95 0.31 0.912200/3 X 0.77 4.85 0.30 1.121600/3 120 0.75 4.18 0.30 0.95

1:1.5 in CB 1000/3 X 0.73 5.15 0.37 1.391500/3 X 0.72 3.75 0.37 1.012000/3 X 0.72 4.31 0.36 1.102500/3 X 0.60 3.56 0.29 0.62

1:2 in CB 1500/3 X 0.72 5.90 0.35 1.502000/3 100 0.70 6.92 0.36 1.762500/3 X 0.53 4.38 0.34 0.793000/3 X 0.62 4.39 0.41 1.11

PTF2:PC70BM1:1.5 in CB 800/3 X 0.72 3.56 0.35 0.91

1000/3 X 0.71 4.74 0.33 1.121500/3 X 0.70 7.67 0.32 1.722000/3 X 0.72 8.70 0.34 2.131000/3 100 0.72 4.97 0.33 1.19800/3 X 0.72 3.56 0.35 0.911000/3 X 0.71 4.78 0.33 1.121500/3 X 0.70 7.67 0.32 1.722000/3 X 0.72 8.70 0.34 2.131000/3 100 0.72 4.97 0.33 1.191500/3 1% DIO 0.51 2.76 0.30 0.422000/3 1% DIO 0.03 2.38 0.21 0.012500/3 1% DIO 0.70 0.04 0.25 0.011500/3 X 0.71 5.2 0.35 1.31800/3 X 0.71 6.24 0.34 1.522000/3 X 0.77 4.91 0.33 1.242000/3 X 0.77 5.72 0.33 1.472000/3 100C 10 M 0.76 5.79 0.33 1.462000/3 120C 10 M 0.74 6.22 0.33 1.542000/3 150C 10 M 0.71 5.12 0.33 1.19

aTotal concentration of the polymer:PC60BM/PC70BM in solution.

S9

Table S4 Performances of photovoltaic devices incorporating the polymer POF2 blended with PC60BM or PC70BM.

POF2:PC60BM/ PC70BM

RPM/ Concentrationa

[mg mL–1]

Anneal [°C]

Voc [V] Jsc [mA cm–2] FF PCE [%]

POF2:PC60BM1:1 in CHCl3 1000/1.5 X 0.71 2.20 0.25 0.39

2000/1.5 X 0.71 2.82 0.26 0.533500/1.5 X 0.68 3.10 0.27 0.572000/1.5 120 0.70 2.27 0.32 0.511200/1 X 0.77 5.33 0.34 1.411800/1 X 0.77 5.49 0.33 1.401000/1 120 0.74 3.22 0.31 0.741200/1 120 0.72 4.97 0.33 1.19

1:1.5 in CHCl3 800/1 X 0.79 4.26 0.33 1.111200/1 X 0.77 4.58 0.34 1.182000/1 X 0.77 4.16 0.35 1.12

1:1.5 in CB 800/1 X 0.77 5.06 0.34 1.311200/1 X 0.67 4.50 0.33 1.002000/1 X 0.49 3.89 0.30 0.581200/1 120 0.66 5.29 0.36 1.25

1:2 in CHCl3 1200/1 X 0.76 3.58 0.37 1.021800/1 X 0.76 3.38 0.39 1.001000/1 120 0.71 3.87 0.30 0.831200/1 120 0.76 4.28 0.32 1.05

POF2:PC70BM1:1.5 in CHCl3 1000/1 X 0.76 3.89 0.40 1.18

2000/1 X 0.77 5.25 0.40 1.601000/1 120 0.75 4.83 0.32 1.182000/1 120 0.76 4.87 0.32 1.18

1:1.5 in CB 2500/3 X 0.77 3.87 0.31 0.912000/3 X 0.76 3.19 0.30 0.721500/3 X 0.77 2.89 0.30 0.672500/3 1% DIO strange2000/3 1% DIO 0.80 4.56 0.41 1.481500/3 1% DIO 0.80 5.19 0.31 1.30

aTotal concentration of the polymer:PC60BM/PC70BM in solution.

S10

Fig. S6. SEM images of blends of the polymers (a) PTF1, (b) POF1, (c) PTF2, and (d) POF2 with PC70BM (1:1.5, w/w).

S11

1H NMR of 5,5´-(5,8-Dibromoquinoxaline-2,3-diyl)bis(1H-pyrrole-2-carbaldehyde) (5)

S12

1H NMR of (N,N´E,N,N´E)-N,N´-((5,5´-(5,8-dibromoquinoxaline-2,3-diyl)bis(1H-pyrrole-5,2-diyl)) bis (methanylylidene))bis(2-fluoroaniline) (AM1)

S13

13C NMR of (N,N´E,N,N´E)-N,N´-((5,5´-(5,8-dibromoquinoxaline-2,3-diyl)bis(1H-pyrrole-5,2-diyl)) bis (methanylylidene))bis(2-fluoroaniline) (AM1)

S14

1H NMR of (N,N´E,N,N´E)-N,N´-((5,5´-(5,8-dibromoquinoxaline-2,3-diyl)bis(1H-pyrrole-5,2diyl))bis(methanylylidene))bis(2,6-difluoroaniline) (AM2)

S15

13C NMR of (N,N´E,N,N´E)-N,N´-((5,5´-(5,8-dibromoquinoxaline-2,3-diyl)bis(1H-pyrrole-5,2diyl))bis(methanylylidene))bis(2,6-difluoroaniline) (AM2)

S16

1H NMR of polymer PTF1

S17

1H NMR of polymer POF1

S18

1H NMR of polymer PTF2

S19

1H NMR of polymer POF2

S20

Elementary analysis mass data of acceptor monomers AM1 and AM2 (i.e., solar F1 and solar F2, respectively)

S21

Elementary analysis mass data of donor monomers DM1 and DM2.

S22

Elementary analysis mass data of polymers PTF1, POF1, PTF2, and POF2 (i.e., THF1-P, OCF1-P, THF2-P, and OCF2-P, respectively)

S23