| 1. |
- Karlsson, P G, et al.
(författare)
-
Interfacial properties of the nanostructured dye-sensitized solid heterojunction TiO2/RuL2(NCS)(2)/CuI
- 2004
-
Ingår i: Journal of Chemical Physics. - : AIP Publishing. - 0021-9606 .- 1089-7690. ; 120:23, s. 11224-11232
-
Tidskriftsartikel (refereegranskat)abstract
- The interfaces of the nanostructured dye-sensitized solid heterojunction TiO2/Ru-dye/CuI have been studied using photoelectron spectroscopy of core and valence levels, x-ray absorption spectroscopy and atomic force microscopy. A nanostructured anatase TiO2 film sensitized with RuL2(NCS)(2) [cis-bis(4,4'-dicarboxy-2,2'-bipyridine)-bis(isothio-cyanato)-ruthenium(II)] was prepared in a controlled way using a novel combined in-situ and ex-situ (Ar atmosphere) method. Onto this film CuI was deposited in-situ. The formation of the dye-CuI interface and the changes brought upon the dye-TiO2 interface could be monitored in a stepwise fashion. A direct interaction between the dye NCS groups and the CuI is evident in the core level photoelectron spectra. Concerning the energy matching of the valence electronic levels, the photoelectron spectra indicate that the dye HOMO overlaps in energy with the Cu 3d-I 5p hydrid states. The CuI grow in the form of particles, which at the initial stages displace the dye molecules causing dye-TiO2 bond breaking. Consequently, the very efficient charge injection channel provided by the dye-TiO2 carboxylic bonding is directly affected for a substantial part of the dye molecules. This may be of importance for the functional properties of such a heterojunction. (C) 2004 American Institute of Physics.
|
|
| 2. |
|
|
| 3. |
- Mahrov, B., et al.
(författare)
-
Comparison of charge accumulation and transport in nanostructured dye-sensitized solar cells with electrolyte or CuSCN as hole conductor
- 2005
-
Ingår i: Solar Energy Materials and Solar Cells. - : Elsevier BV. - 0927-0248 .- 1879-3398. ; 88:4, s. 351-362
-
Tidskriftsartikel (refereegranskat)abstract
- The charge transport properties of the dye-sensitized solar cells consisting of Ru(dcbpyH(2))(2)(NCS)(2)-sensitized nanostructured TiO2 with either redox electrolyte or CuSCN as hole conductor have been compared. The electron transport time and the electron charge in the TiO2 varies in a similar way with the incident light intensity for both hole conductors: electron transport becomes faster and electron accumulation increases with increasing light intensity. Electron transport in the CuSCN-based cells is significantly faster than in electrolyte cells under conditions where the accumulated charge is equal. An ultra-thin aluminum oxide layer on the nanocrystalline titanium oxide has a beneficial effect as it reduces the recombination and increases the open-circuit potential.
|
|
| 4. |
- Mahrov, B., et al.
(författare)
-
Photovoltage study of charge injection from dye molecules into transparent hole and electron conductors
- 2004
-
Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 84:26, s. 5455-5457
-
Tidskriftsartikel (refereegranskat)abstract
- Transient and spectral photovoltage (PV) have been investigated for charge injection from a dye [Ru(dcbpyH(2))(2)(NCS)(2)] into transparent hole ( CuSCN, CuI, CuAlO2) and electron ( TiO2, SnO2:F) conductors. The PV signal rises to a maximum within 10 ns to 10 mus, depending on the transparent hole or electron conductor and on the mechanism of charge separation. The efficiency of hole and electron injection is of the same order while the effective lifetimes of injected charge vary between several mus and 1 ms for the samples used. The thresholds for charge injection from the dye range between 1.6 and 1.8 eV depending on the material on which the dye is adsorbed.
|
|
| 5. |
|
|
