Investigation of the influence of coadsorbent dye upon the interfacial structure of dye-sensitized solar cells

Journal Article · Fri Nov 07 00:00:00 EST 2014 · Journal of Chemical Physics

DOI:https://doi.org/10.1063/1.4900640· OSTI ID:22415326

Miyano, K. ^[1]; Yanagida, M. ^[1]; Han, L. ^[2]

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1. Global Research Center for Environment and Energy based on Nanomaterials Science (GREEN), National Institute of Materials Science (NIMS), 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047 (Japan)
2. Photovoltaic Materials Unit, NIMS, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047 (Japan)

The interface between Ru(tcterpy)(NCS){sub 3}TBA{sub 2} [black dye (BD); tcterpy = 4,4{sup ′},4{sup ″}-tricarboxy-2,2{sup ′}:6{sup ′},2{sup ″}-terpyridine, NCS = thiocyanato, TBA = tetrabutylammonium cation] and nanocrystalline TiO{sub 2}, as found in dye-sensitized solar cells, is investigated by soft-X-ray synchrotron radiation and compared with the adsorption structure of cis-Ru(Hdcbpy){sub 2}(NCS){sub 2}TBA{sub 2} (N719; dcbpy = 4,4{sup ′}-dicarboxy-2,2{sup ′}-bipyridine) on TiO{sub 2} to elucidate the relationship between the adsorption mode of BD and the photocurrent with and without coadsorbed indoline dye D131. The depth profile is characterized with X-ray photoelectron spectroscopy and S K-edge X-ray absorption fine structure using synchrotron radiation. Both datasets indicate that one of the isothiocyanate groups of BD interacts with TiO{sub 2} via its S atom when the dye is adsorbed from a single-component solution. In contrast, the interaction is slightly suppressed when D131 is coadsorbed, indicated by the fact that the presence of D131 changes the adsorption mode of BD. Based upon these results, the number of BD dye molecules interacting with the substrate is shown to decrease by 10% when D131 is coadsorbed, and the dissociation is shown to be related to the short-circuit photocurrent in the 600–800 nm region. The design of a procedure to promote the preferential adsorption of D131 therefore leads to an improvement of the short-circuit current and conversion efficiency.

• OSTI ID: 22415326
• Journal Information: Journal of Chemical Physics, Vol. 141, Issue 17; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
ABSORPTION
ADSORPTION
BIPYRIDINES
CATIONS
CRYSTALS
DISSOCIATION
DYES
EFFICIENCY
ELECTRICAL FAULTS
FINE STRUCTURE
INTERACTIONS
ISOTHIOCYANATES
NANOSTRUCTURES
SOFT X RADIATION
SOLAR CELLS
SOLUTIONS
SUBSTRATES
SYNCHROTRON RADIATION
TITANIUM OXIDES
X-RAY PHOTOELECTRON SPECTROSCOPY