Simultaneous Enhancement of Efficiency and Stability of ...
Supporting Information for:
Simultaneous Enhancement of Efficiency and Stability of Phosphorescent OLEDs Based on Efficient Förster Energy Transfer from Interface Exciplex Dongdong Zhang, Minghan Cai, Yunge Zhang, Zhengyang Bin, Deqiang Zhang, Lian Duan* Key Lab of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing 100084, China. *Correspondence to: E-mail address: [email protected]: +86 10 62795137; Tel: +86 10 62782197.
S-1
1. Photoluminance spectra of CzTrz. RT 77k emission
1.0
Intensity (a.u.)
0.8
0.6
0.4
0.2
0.0 350
400
450
500
550
600
650
700
Wavelength (nm)
Figure S1: The emission of CzTrz at room temperature (RT) and 77k. 2. Calculation of the ratio of the prompt and delayed parts of exciplex emission. The intensity ratio between prompt (r1) and delayed (r2) components were determinded using emission lifetime (τ1,τ2) and fitting parameter (A1, A2) as follow. −
I (t ) = Ae 1
t
τ1
−
+ Ae 2
r1 =
A1τ 1 A1τ 1 + A2τ 2
r2 =
A2τ 2 A1τ 1 + A2τ 2
t
τ2
The A1, τ1, A2 and τ2 were obtained from the fitting of the decay curves, which were 4932, 68 ns, 1510 and 2000 ns, respectively. And thus the ratio of the delayed part can be calculated to be 90%.
3. The current density of the single-carrier devices. hole-only electron-only
2
current density (A/m )
3000
2000
1000
0 0
5
10
15
20
voltage (V)
Figure S2: The current density-voltage of the hole-only and electron-only devices. The structures of the single-carrier devices are ITO/HATCN (10 nm)/ CzTrz (100 nm)/ HATCN (10 nm)/ Al (150 nm) and ITO/Bphen (10 nm)/ CzTrz (100 nm)/ Bphen (10 nm)/ LiF (0.5 nm)/ Al (150 nm) for hole- and electron-only devices, respectively. 4. The performance of devices with interface exciplex (EML of 30 nm).
S-2
80
a
10000
b
Power efficiency (lm/W)
2
Brightness (cd/m )
70
1000
1% 2% 3% 5%
100
10
60 50 40 30
1% 2% 3% 5%
20 10
1
0
3
4
5
6
7
8
0
Voltage (V)
2500
5000
2
7500
10000
Brightness (cd/m )
Figure S3: (a) The brightness-voltage curves of the devices. (b) The power efficiency-brightness curves of the devices. The device structures are ITO/ HATCN (5 nm)/ NPB (40nm)/ TCTA (20 nm)/ CzTrz (30 nm): PO-01/ BPhen (40 nm)/ LiF (0.5 nm)/ Al (150 nm). 5. The performance of devices with interface exciplex (EML of 10 nm). 1000
b
a
10000
2
Brightness (cd/m )
2
Current density (A/m )
100 1000
1% 2% 3% 4%
100
10
1
10
1% 2% 3% 4%
1
0.1
0.01 2
3
4
5
6
7
8
3
Voltage (V) 90
70
5
Voltage (V)
d
50 40
1% 2% 3% 4%
30 20
6
7
1% 2% 3% 5%
0.8
60
Intensity (a.u.)
Power efficiency (lm/W)
1.0
c
80
4
0.6
0.4
0.2
10 0
0.0 0
2500
5000
7500
10000
400
2
Brightness (cd/m )
500
600
Wavelength (nm)
700
Figure S4: (a) The brightness-voltage curves of the devices. (b) The current efficiency-voltage curves of the devices. (c) The power efficiency-brightness curves of the devices. (d) The spectra of the devices. The device structures are ITO/ HATCN (5 nm)/ NPB (40nm)/ TCTA (20 nm)/ CzTrz (10 nm): PO-01/ BPhen (40 nm)/ LiF (0.5 nm)/ Al (150 nm). 6. The performance of devices with exciplex free.
S-3
1000
10000
a
b 2
Current density (A/m )
2
Brightness (cd/m )
100
1000
1% 2% 3% 4%
100
10
1
1% 2% 3% 5%
10
1
0.1
4
5
6
7
8
9
4
5
6
7
8
9
Voltage (V)
Voltage (V) 30
Power efficiency (lm/W)
25
d
50
c
EQE
20
15
1% 2% 3% 5%
10
40
30
20
1% 2% 3% 5%
10
5
0
0 0
1.0
2500
5000
2
Brightness (cd/m )
0
10000
2500
5000
7500
10000
2
Brightness (cd/m )
1% 2% 3% 5%
e
0.8
Intensity (a.u.)
7500
0.6
0.4
0.2
0.0 400
500
600
700
Wavelength (nm)
Figure S5: (a) The brightness-voltage curves of the devices. (b) The current efficiency-voltage curves of the devices. (c) The EQE-brightness curves of the devices. (d) The power efficiency-brightness curves of the devices. (e) The spectra of the devices. The device structures are ITO/ HATCN (5 nm)/ NPB (40nm)/ TCTA (10 nm)/ mCP (10 nm)/ CzTrz (30 nm): PO-01/ BPhen (40 nm)/ LiF (0.5 nm)/ Al (150 nm). 7. The emission spectra of devices with inserted CzTrz layer.
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1.0
2 nm 4 nm 8 nm 12 nm
Intensity (a.u.)
0.8
0.6
0.4
0.2
0.0 400
500
600
700
Wavelength (nm)
Figure S6: The emission spectra of the devices with inserted CzTrz layer. The device structures are ITO/ HATCN (5 nm)/ NPB (40nm)/ TCTA (20 nm)/ CzTrz (x nm)/ CzTrz (30 nm): PO-01/ BPhen (40 nm)/ LiF (0.5 nm)/ Al (150 nm). 8. The performance of devices with bulk exciplex. 1000
a
10000
b
2
Brightness (cd/m )
2
Current density (A/m )
100 1000
1% 2% 3% 5%
100
10
1% 2% 3% 5%
10
1
0.1
1 1
2
3
4
5
6
7
3
8
4
5
Voltage (V)
6
7
8
Voltage (V)
70
1% 2% 3% 4%
d
0.8
50
Intensity (a.u.)
Power efficiency (lm/W)
1.0
c
60
40
30
1% 2% 3% 5%
20
10
0.6
0.4
0.2
0.0
0 0
2500
5000
7500
400
10000
500
600
700
Wavelength (nm)
2
Brightness (cd/m )
Figure S7: (a) The brightness-voltage curves of the devices. (b) The current efficiency-voltage curves of the devices. (c) The power efficiency-brightness curves of the devices. (d) The spectra of the devices. The device structures are ITO/ HATCN (5 nm)/ NPB (40nm)/ TCTA (20 nm)/ TCTA: CzTrz: PO-01 (30 nm)/ BPhen (40 nm)/ LiF (0.5 nm)/ Al (150 nm). 9. The recombination mechnisims of devices with exciplex.
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Figure S8: (a) The recombination mechanism of devices with interface exciplex. (b) The recombination mechanism of devices with bulk exciplex. Process 1 stands for the formation of the excited states of CzTrz while process 2 stands for the formation of interface exciplex. Process 1’ stands for the formation of the bulk exciplex, process 2’ stands for the formation of the excited states of CzTrz while process 3’ is the formation of the excited states of TCTA.
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Simultaneous Enhancement of Efficiency and Stability of Phosphorescent OLEDs Based on Efficient Förster Energy Transfer from Interface Exciplex Dongdong Zhang, Minghan Cai, Yunge Zhang, Zhengyang Bin, Deqiang Zhang, Lian Duan* Key Lab of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing 100084, China. *Correspondence to: E-mail address: [email protected]: +86 10 62795137; Tel: +86 10 62782197.
S-1
1. Photoluminance spectra of CzTrz. RT 77k emission
1.0
Intensity (a.u.)
0.8
0.6
0.4
0.2
0.0 350
400
450
500
550
600
650
700
Wavelength (nm)
Figure S1: The emission of CzTrz at room temperature (RT) and 77k. 2. Calculation of the ratio of the prompt and delayed parts of exciplex emission. The intensity ratio between prompt (r1) and delayed (r2) components were determinded using emission lifetime (τ1,τ2) and fitting parameter (A1, A2) as follow. −
I (t ) = Ae 1
t
τ1
−
+ Ae 2
r1 =
A1τ 1 A1τ 1 + A2τ 2
r2 =
A2τ 2 A1τ 1 + A2τ 2
t
τ2
The A1, τ1, A2 and τ2 were obtained from the fitting of the decay curves, which were 4932, 68 ns, 1510 and 2000 ns, respectively. And thus the ratio of the delayed part can be calculated to be 90%.
3. The current density of the single-carrier devices. hole-only electron-only
2
current density (A/m )
3000
2000
1000
0 0
5
10
15
20
voltage (V)
Figure S2: The current density-voltage of the hole-only and electron-only devices. The structures of the single-carrier devices are ITO/HATCN (10 nm)/ CzTrz (100 nm)/ HATCN (10 nm)/ Al (150 nm) and ITO/Bphen (10 nm)/ CzTrz (100 nm)/ Bphen (10 nm)/ LiF (0.5 nm)/ Al (150 nm) for hole- and electron-only devices, respectively. 4. The performance of devices with interface exciplex (EML of 30 nm).
S-2
80
a
10000
b
Power efficiency (lm/W)
2
Brightness (cd/m )
70
1000
1% 2% 3% 5%
100
10
60 50 40 30
1% 2% 3% 5%
20 10
1
0
3
4
5
6
7
8
0
Voltage (V)
2500
5000
2
7500
10000
Brightness (cd/m )
Figure S3: (a) The brightness-voltage curves of the devices. (b) The power efficiency-brightness curves of the devices. The device structures are ITO/ HATCN (5 nm)/ NPB (40nm)/ TCTA (20 nm)/ CzTrz (30 nm): PO-01/ BPhen (40 nm)/ LiF (0.5 nm)/ Al (150 nm). 5. The performance of devices with interface exciplex (EML of 10 nm). 1000
b
a
10000
2
Brightness (cd/m )
2
Current density (A/m )
100 1000
1% 2% 3% 4%
100
10
1
10
1% 2% 3% 4%
1
0.1
0.01 2
3
4
5
6
7
8
3
Voltage (V) 90
70
5
Voltage (V)
d
50 40
1% 2% 3% 4%
30 20
6
7
1% 2% 3% 5%
0.8
60
Intensity (a.u.)
Power efficiency (lm/W)
1.0
c
80
4
0.6
0.4
0.2
10 0
0.0 0
2500
5000
7500
10000
400
2
Brightness (cd/m )
500
600
Wavelength (nm)
700
Figure S4: (a) The brightness-voltage curves of the devices. (b) The current efficiency-voltage curves of the devices. (c) The power efficiency-brightness curves of the devices. (d) The spectra of the devices. The device structures are ITO/ HATCN (5 nm)/ NPB (40nm)/ TCTA (20 nm)/ CzTrz (10 nm): PO-01/ BPhen (40 nm)/ LiF (0.5 nm)/ Al (150 nm). 6. The performance of devices with exciplex free.
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1000
10000
a
b 2
Current density (A/m )
2
Brightness (cd/m )
100
1000
1% 2% 3% 4%
100
10
1
1% 2% 3% 5%
10
1
0.1
4
5
6
7
8
9
4
5
6
7
8
9
Voltage (V)
Voltage (V) 30
Power efficiency (lm/W)
25
d
50
c
EQE
20
15
1% 2% 3% 5%
10
40
30
20
1% 2% 3% 5%
10
5
0
0 0
1.0
2500
5000
2
Brightness (cd/m )
0
10000
2500
5000
7500
10000
2
Brightness (cd/m )
1% 2% 3% 5%
e
0.8
Intensity (a.u.)
7500
0.6
0.4
0.2
0.0 400
500
600
700
Wavelength (nm)
Figure S5: (a) The brightness-voltage curves of the devices. (b) The current efficiency-voltage curves of the devices. (c) The EQE-brightness curves of the devices. (d) The power efficiency-brightness curves of the devices. (e) The spectra of the devices. The device structures are ITO/ HATCN (5 nm)/ NPB (40nm)/ TCTA (10 nm)/ mCP (10 nm)/ CzTrz (30 nm): PO-01/ BPhen (40 nm)/ LiF (0.5 nm)/ Al (150 nm). 7. The emission spectra of devices with inserted CzTrz layer.
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1.0
2 nm 4 nm 8 nm 12 nm
Intensity (a.u.)
0.8
0.6
0.4
0.2
0.0 400
500
600
700
Wavelength (nm)
Figure S6: The emission spectra of the devices with inserted CzTrz layer. The device structures are ITO/ HATCN (5 nm)/ NPB (40nm)/ TCTA (20 nm)/ CzTrz (x nm)/ CzTrz (30 nm): PO-01/ BPhen (40 nm)/ LiF (0.5 nm)/ Al (150 nm). 8. The performance of devices with bulk exciplex. 1000
a
10000
b
2
Brightness (cd/m )
2
Current density (A/m )
100 1000
1% 2% 3% 5%
100
10
1% 2% 3% 5%
10
1
0.1
1 1
2
3
4
5
6
7
3
8
4
5
Voltage (V)
6
7
8
Voltage (V)
70
1% 2% 3% 4%
d
0.8
50
Intensity (a.u.)
Power efficiency (lm/W)
1.0
c
60
40
30
1% 2% 3% 5%
20
10
0.6
0.4
0.2
0.0
0 0
2500
5000
7500
400
10000
500
600
700
Wavelength (nm)
2
Brightness (cd/m )
Figure S7: (a) The brightness-voltage curves of the devices. (b) The current efficiency-voltage curves of the devices. (c) The power efficiency-brightness curves of the devices. (d) The spectra of the devices. The device structures are ITO/ HATCN (5 nm)/ NPB (40nm)/ TCTA (20 nm)/ TCTA: CzTrz: PO-01 (30 nm)/ BPhen (40 nm)/ LiF (0.5 nm)/ Al (150 nm). 9. The recombination mechnisims of devices with exciplex.
S-5
Figure S8: (a) The recombination mechanism of devices with interface exciplex. (b) The recombination mechanism of devices with bulk exciplex. Process 1 stands for the formation of the excited states of CzTrz while process 2 stands for the formation of interface exciplex. Process 1’ stands for the formation of the bulk exciplex, process 2’ stands for the formation of the excited states of CzTrz while process 3’ is the formation of the excited states of TCTA.
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