Post on 27-Jun-2020
transcript
1938-8
Workshop on Nanoscience for Solar Energy Conversion
Emilio PALOMARES
27 - 29 October 2008
Institute of Chemical Research of CataloniaAvinguda Paisos Catalans 16
43007 TarragonaSpain
Charge Recombination Studies in Hybrid Molecular Photovoltaic Devices
Charge Recombination Dynamics in
Molecular Photovoltaic Devices.
Dr. Emilio Palomares. ICREA Research Professor
Institute of Chemical Research of Catalonia (ICIQ).
e-mail: epalomares@iciq.es
Always Different Interfaces
Molecular Solar Cells
Photons in....Electrons Out
Always Different Interfaces
Molecular Solar Cells
Photons in....Electrons Out
Always Different Interfaces
Molecular Solar Cells
Photons in....Electrons Out
Always Different Interfaces
Molecular Solar Cells
Photons in....Electrons Out
Always Different Interfaces
Molecular Solar Cells
Photons in....Electrons Out
Dye Sensitised Solar Cells
"Blend" Solar Cells
Two different approaches
Different Photovoltaic Devices
HTM/ DYE+ Regeneration
ETIO2/ DYE Injection
ETIO2/ HTM RECOMBINATION
ETIO2/ DYE+
RECOMBINATION
L-TAS
TCSPC
Charge Transfer Processes
TPV
Charge Transfer Processes
E
HOMO
LUMO
ETIO2/ DYE+ injection
Charge Transfer Processes
E
HOMO
LUMO
ETIO2/ DYE+ injection
Charge Transfer Processes
E
HOMO
LUMO
ETIO2/ DYE+ injection
Charge Transfer Processes
E
HOMO
LUMO
ETIO2/ DYE+ injection
E
HOMO
LUMO
ETIO2/ DYE+ recombination
y = y0(�� /t )�
Fitting to KWW function
Charge Transfer Processes
E
HOMO
LUMO
ETIO2/ DYE+ recombination
y = y0(�� /t )�
Fitting to KWW function
Charge Transfer Processes
E
HOMO
LUMO
ETIO2/ DYE+ recombination
y = y0(�� /t )�
Fitting to KWW function
Charge Transfer Processes
E
HOMO
LUMO
ETIO2/ DYE+ RECOMBINATION
Charge Transfer Processes
E
HOMO
LUMO
ETIO2/ HTM RECOMBINATION
HTM
Charge Transfer Processes
E
HOMO
LUMO
ETIO2/ HTM RECOMBINATION
HTM
Charge Transfer Processes
E
HOMO
LUMO
ETIO2/ HTM RECOMBINATION
HTM
Charge Transfer Processes
E
HOMO
LUMO
HTM
HTM/ DYE+ Regeneration
Charge Transfer Processes
E
HOMO
LUMO
HTM
HTM/ DYE+ Regeneration
Charge Transfer Processes
E
HOMO
LUMO
HTM
HTM/ DYE+ Regeneration
Charge Transfer Processes
E
HOMO
LUMO
HTM
Overall charge transfer processes
Charge Transfer Processes
E
HOMO
LUMO
HTM
Overall charge transfer processes
10-12-10-9s
Charge Transfer Processes
E
HOMO
LUMO
HTM
Overall charge transfer processes
10-12-10-9s
10-4-10-6s
Charge Transfer Processes
E
HOMO
LUMO
HTM
Overall charge transfer processes
10-12-10-9s
10-4-10-6s10-3-101 s
Charge Transfer Processes
E
HOMO
LUMO
HTM
Overall charge transfer processes
10-12-10-9s
10-4-10-6s10-3-101 s
10-10-10-9 s
Charge Transfer Processes
Device Characterisation
IPCE =Iph �1240
� � P0�100
�device = Isc �Voc � FF
Charge Transfer Processes
Device Characterisation
IPCE =Iph �1240
� � P0�100
�device = Isc �Voc � FF
Charge Transfer Processes
Device Characterisation
IPCE =Iph �1240
� � P0�100
�device = Isc �Voc � FF
Charge Transfer Processes
Controlling "Dark" Electron transfer Reaction
ICIQ's Research
Controlling "Dark" Electron transfer Reaction
Dye absorption Kinetics
A = Amax (1� exp(�Kadst))
Lagergren's Equation
ICIQ's Research
Controlling "Dark" Electron transfer Reaction
Dye Injection kinetics
y = y0(�� /t )�
Injection into TiO2 CB occurs before 100 ps
Injection on Devices is slower. Nonetheless still faster than 250 ps
ICIQ's Research
Controlling "Dark" Electron transfer Reaction
Dye Injection kinetics
y = y0(�� /t )�
Injection into TiO2 CB occurs before 100 ps
Injection on Devices is slower. Nonetheless still faster than 250 ps
ICIQ's Research
Controlling "Dark" Electron transfer Reaction
TiO2/Dye+ charge transfer kinetics
y = y0(�� /t )�
TiO2/dye+ recombination half-lifetime ~3 x 10-4 s.TTT
ICIQ's Research
Controlling "Dark" Electron transfer Reaction
TiO2/Dye+ charge transfer kinetics
y = y0(�� /t )�
TiO2/dye+ recombination half-lifetime ~3 x 10-4 s.TTT
ICIQ's Research
Controlling "Dark" Electron transfer Reaction
TiO2/Dye+ charge transfer kinetics
y = y0(�� /t )�
TiO2/dye+ recombination half-lifetime ~3 x 10-4 s.TTT
ICIQ's Research
Controlling "Dark" Electron transfer Reaction
TiO2/Dye+ charge transfer kinetics
y = y0(�� /t )�
TiO2/dye+ recombination half-lifetime ~3 x 10-4 s.TTT
ICIQ's Research
Controlling "Dark" Electron transfer Reaction
TiO2/electrolyte+ charge transfer kinetics
No TiO2 CB shift. No effect on the DOS by alkyl chains
Slow "dark" recombination dynamics
ICIQ's Research
Controlling "Dark" Electron transfer Reaction
TiO2/electrolyte+ charge transfer kinetics
No TiO2 CB shift. No effect on the DOS by alkyl chains
Slow "dark" recombination dynamics
ICIQ's Research
Enhanced device efficiency
DSSC Devices
Increase in Current
Increase in voltage
ICIQ's Research
1
10
100
1000
10000
100000
0 5 10 15 20
PI1/Al2O
3
PI1/TiO2
Em
iss
ion
Co
un
ts (
a.u
.)
Time (ns)
Dye Sensitised Solar Cells
Dye Sensitised Solar Cells
0
1
2
3
4
5
6
7
550 600 650 700 750 800
PI1/Al2O
3
PI1/TiO2
Em
iss
ion
In
ten
sit
y (
a.u
.)
Wavelength (nm)
Dye Sensitised Solar Cells
0
1 10-4
2 10-4
3 10-4
4 10-4
5 10-4
10-6
10-5
10-4
10-3
10-2
10-1
15 minutes4 hours14 hours
� O
.D.
Time (s)
SAME WL
0
5 10-5
1 10-4
1.5 10-4
2 10-4
10-6
10-5
10-4
10-3
10-2
10-1
15 minutes4 hours14 hours
� O
.D.
Time (s)
SAME OD
Dye Sensitised Solar Cells
0
2
4
6
8
10
0 0.1 0.2 0.3 0.4 0.5 0.6
1 hour
4 hours
5 hours
14 hours
Ph
oto
cu
rre
nt
(mA
)
Voltage (V)
0.01
0.1
1
0.2 0.25 0.3 0.35 0.4 0.45 0.5
1 hour
14 hours
5 hours
Reco
mb
inati
on
Lif
eti
me (
s)
Cell Voltage (V)
ICIQ-Dyes
phenanthroline heteroleptic Ru(II) complexes
Dye Sensitised Solar Cells
MO
Dye Sensitised Solar Cells
-2.0
-3.0
-4.0
-5.0
E(eV)
(1.67) (1.70) (1.68)
(1.29)
(-2.97)
(-4.64)
(-2.89)
(-4.59)
(-2.91)
(-4.59)
(-3.54)
(-4.83) ( )
( 2 97)(-2 89)
( )
(-((((((( 4
-2.919191919119991111991199119111)))))))))))))))))))))))))))))))))))))
83)
Phen Me-PhenNH2-Phen NO2-Phen
Electron Injection
Dye Sensitised Solar Cells
Electron Injection
Dye Sensitised Solar Cells
e--TiO2/Dye+ Recombination
Dye Sensitised Solar Cells
0
5 10-5
0,0001
0,00015
0,0002
0,00025
0,0003
0,00035
0,0004
10-6
10-5
0,0001 0,001 0,01 0,1
N719
AR20
AR24
AR25
AR27
�O
.D.
Time (s)
0
6 10-5
0,00012
0,00018
0,00024
0,0003
600 650 700 750 800 850 900 950
100us
500us
�O
.D. (a
.u.)
Wavelength (nm)
e--TiO2/Dye+ Recombination
Dye Sensitised Solar Cells
0
2 10-5
4 10-5
6 10-5
8 10-5
0,0001
10-6
10-5
10-4
10-3
10-2
10-1
N719
TiO2
Cell Dark
White Light 800
White Light 999
Time (s)
� O
.D.
0
4 10-5
8 10-5
0,00012
0,00016
0,0002
0,00024
0,00028
10-6
10-5
10-4
10-3
10-2
10-1
AR25/TiO2:l
probe=800 nm
AR25/DSSC:lprobe
=800 nm
AR25/DSSC:lprobe
=1000 nm
Time (s)
� O
.D.
e--TiO2/Dye+ Recombination
Dye Sensitised Solar Cells
0
5 10-5
0,0001
0,00015
0,0002
10-6
10-5
10-4
10-3
10-2
10-1
AR24a/TiO2
:�probe
=800nm
AR24a/DSSC2
:�probe
=800nm
AR24a/DSSC2
:�probe
=1000nm
�O
.D.
Time (s)
0
4 10-5
8 10-5
0,00012
0,00016
0,0002
0,00024
0,00028
10-6
10-5
10-4
10-3
10-2
10-1
AR25/TiO2:l
probe=800 nm
AR25/DSSC:lprobe
=800 nm
AR25/DSSC:lprobe
=1000 nm
Time (s)
� O
.D.
Cell Characterisation
Dye Sensitised Solar Cells
-2
0
2
4
6
8
10
12
14
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7
Jsc (
mA
/cm
2)
Voltage (V)
DSSC 208
�: 6,10 %
Voc: 0,66 V
Jsc: 13,55 mA/cm2
FF: 66,60 %
Device Area: 0,152 cm2
Dye: AR20
Electrolyte: AF04
Ligth: 100mW/cm2
Layers: TiO2 TiCl
4 (16+4) -2
-1
0
1
2
0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8
AR20
AR24-16
AR24-18
AR25
AR27-16
AR27-18
Ph
oto
cu
rre
nt
(mA
)
Voltage (V)
Dye Sensitised Solar Cellse--TiO2/Electrolyte+ Recombination
0
5 10-5
0,0001
0,00015
0,0002
0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8
AR20
AR24a
AR24b
AR25
AR27b
AR27b
N719
Ch
arg
e (
C)
/cm
2
Voltage (V)
*
0
0,5
1
1,5
2
0 0,004 0,008 0,012 0,016 0,02
AR25
AR27
AR20
AR24
No
rma
lize
d I
nte
ns
ity
(a
.u.)
Time (s)
Organic solar cells
-- -
+ +
-----
-
+ +++
+
+++ ++
+
+
++
++
+++
-----
--------------
+
+++ ++
+
-
+
HOMO HOMO
LUMO LUMO
Organic solar cellsP3HT/PCBM d-TiO2/ P3HT/PCBM
Organic solar cells P3HT/PCBM
10-5
0,0001
0,001
10-6
10-5
0,0001 0,001 0,01
1:07
1:0.5
1:1
� O
.D.
Time (s)
Charge recombination
dynamics
dependent on P3HT/PCBM
ratio
Organic solar cellsITO/pentacene/C60/BCP/Al
-10
-5
0
5
-0.4 -0.2 0 0.2 0.4
0,1 Sun
1 Sun
dark
Js
c (
mA
/cm
2)
Voc (V)
FF=44.7%
�=0.54%
Voc=0.285
Isc=4.23mA/cm2
PENTACENE
ITO
4.8EV5.0EV C60
4.5EV
6.2EV
3.0EV
X.X
AL
BCP
Organic solar cellsITO/C60: ZnPc/DINPB/NDP2-DiNPB/NDP2-ZnPc/Au/Ag/Au
0
2
4
6
8
10
12
0 0.1 0.2 0.3 0.4 0.5 0.6
0.1 sun
0.5 sun
1 sun
Jsc(m
A)
Voltage (V)
�=2.70%
�=3.85%
�=3.59%
1
10
5 1016
1 1017
1.5 1017
2 1017
2.5 1017
3 1017
tau teoric
��
n (
μs
)
n (cm-3
)
Acknowledgments
Research Group Members and collaborators
Funding Agencies
Private Funding
Acknowledgments
Research Group Members and collaborators
Funding Agencies
Private Funding
Acknowledgments
Research Group Members and collaborators
Funding Agencies
Private Funding
Acknowledgments
Research Group Members and collaborators
Funding Agencies
Private Funding