Celle Solari
Fotosensibilizzate:
Comprendere il meccanismo,
migliorare l’efficienza
Filippo De Angelis
Istituto CNR di Scienze e Tecnologie Molecolari
(ISTM), c/o Dipartimento di Chimica, Università di
Perugia, I-06123 Perugia, Italy
The problem is to gather solar light at an effective cost!
Solar Emission
CONDUCTION
1100 nm
SILICON 1.12 eV
TiO2
VALENCE
CONDUCTION
SILICON
TiO2
300
4.13
Wavelength (nm)
Energy (eV)
2500
0.50
380 nm
3.20 eV
VALENCE
Dye-sensitized solar cells: =11.3 %
Ru(II)-polypyridyl sensitizers on TiO2
=iph Voc ff / Is
iph  rate of electron injection
Voc  position of the conduction band
(N3-N34-)
Acidic COOH groups
O’Regan, B.; Grätzel, M. Nature, 1991, 353, 737 ; M. Grätzel, Nature, 2001, 414, 338.
Dye-Sensitized Solar Cells: Flexible, colorful,
transparent PVs
ERG, Permasteelisa, Dyesol IT, Tozzi Renewable
Energy, Targetti Sankey, Colorobbia
Michael Grätzel
James Durrant
Arthur J. Nozik
Absorption spectrum of N719 in water:
Intensity (arb. units)
*
Exp.
Theor.
HOMO-3
MLCT (II)
MLCT (I)
Energy (eV)
S. Fantacci, F. De Angelis, A. Selloni
F. De Angelis, S. Fantacci, A. Selloni
F. De Angelis, S. Fantacci, M.K. Nazeeruddin
F. De Angelis,. S. Fantacci, M. Grätzel et al.
HOMO
LUMO
J. Am. Chem. Soc. 2003, 125, 4381.
Chem. Phys. Lett. 2004, 389, 204.
Chem. Phys. Lett. 2005, 415, 115.
J. Am. Chem. Soc. 2005, 127, 16835.
Modeling of TiO2 nanoparticles:
Stoichiometric anatase (TiO2)38 and (TiO2)82 clusters of 1 and
2 nm dimensions exposing (101) surfaces
20.5 Å
18.5 Å
Ti82O164
B3LYP/3-21g*
B3LYP/DZVP
TD-DFT gap in water
3.20/3.41 eV
3.13/3.35 eV
Experimental gap in acqueous solutions: 3.20 – 3.30 eV
F. De Angelis, A. Tilocca, A. Selloni J. Am. Chem. Soc. 2004, 126, 15024
Alignment of excited state potentials:
-3.5
E (eV)
-4.0
E(S+/S*)
-3.42
E(S+/S*)
-3.40
ES =0.62
ET =0.42
ES =0.63
ET =0.44
E(S+/S*)
-3.631
ES=0.40
ET =0.19
-4.04
TiO2 C.B
1.95
(1.75)
2.00
(1.80)
1.77 (1.56)
-5.0
3.13
E(S+/S)
-5.5
AA
BB
AB
N719
-6.5
Exp.
TiO2 C.B
-7.0
-7.5
TiO2
Theor.
- 4.0/-4.2 eV
TiO2 vs. NHE
- 4.04 eV
-0.50 V
N719vs. NHE -0.98 V
(-3.42/-3.22eV)
E=0.48 V ET =0. 435eV
F. De Angelis, S. Fantacci, A. Selloni, Nanotechnology, 2008, 19, 424002.
Charge generation and injection mechanisms:
N3 + hν
N3*
N3+ + 1 e -
hν
1e-
F. De Angelis, S. Fantacci, A. Selloni, M. Grätzel J. Am. Chem. Soc. 2007, 129, 10320.
From Design to Prototypes:
The TECNO-SOLART spin-off
Regione dell’Umbria
Comune di Perugia
Approved Projects:
 MIUR PRIN 2008
ongoing
 IIT-SEED 2009
ongoing
Dyesol 2009
ongoing
ESF 2009
ongoing
EU-FP7: ENERGY-2009-India
2010
EU-FP7: NMP-2009
2010
Submitted Projects:
PON 2010
Cariplo 2010
MATTM 2010
(Tozzi Renable Energy)
(Fondazione Cariplo)
(Targetti Sankey/Daunia
Solar Cells)