Effect of Co-Adsorbate and Hole Transporting Layer on the Photoinduced Charge Separation at the TiO2-Phthalocyanine Interface
| Autor: | María Medel, Essi Tervola, Tomás Torres, Kirsi Virkki, Nikolai V. Tkachenko |
|---|---|
| Přispěvatelé: | UAM. Departamento de Química Orgánica, Instituto de Investigación Avanzada en Ciencias Químicas (IADChem) |
| Rok vydání: | 2018 |
| Předmět: |
Materials science
General Chemical Engineering Photoreactions 02 engineering and technology 010402 general chemistry Photochemistry 01 natural sciences lcsh:Chemistry Charge separation (CS) chemistry.chemical_compound Layer of TiO2nanoparticle Pc-sensitized DSSC Absorption (electromagnetic radiation) Spectroscopy Transporting material Photocurrent Energy conversion efficiency Química General Chemistry Phthalocyanines (Pcs) 021001 nanoscience & nanotechnology Tin oxide 0104 chemical sciences Photoinduced charge separation chemistry lcsh:QD1-999 Phthalocyanine Quantum efficiency 0210 nano-technology Visible spectrum |
| Zdroj: | Repositorio Institucional del Instituto Madrileño de Estudios Avanzados en Nanociencia instname ACS Omega, Vol 3, Iss 5, Pp 4947-4958 (2018) Biblos-e Archivo. Repositorio Institucional de la UAM |
| Popis: | Understanding the primary processes of charge separation (CS) in solid-state dye-sensitized solar cells (DSSCs) and, in particular, analysis of the efficiency losses during these primary photoreactions is essential for designing new and efficient photosensitizers. Phthalocyanines (Pcs) are potentially interesting sensitizers having absorption in the red side of the optical spectrum and known to be efficient electron donors. However, the efficiencies of Pc-sensitized DSSCs are lower than that of the best DSSCs, which is commonly attributed to the aggregation tendency of Pcs. In this study, we employ ultrafast spectroscopy to discover why and how much does the aggregation affect the efficiency. The samples were prepared on a standard fluorine-doped tin oxide (FTO) substrates covered by a porous layer of TiO2nanoparticles, functionalized by a Pc sensitizer and filled by a hole transporting material (Spiro-MeOTAD). The study demonstrates that the aggregation can be suppressed gradually by using co-adsorbates, such as chenodeoxycholic acid (CDCA) and oleic acid, but rather high concentrations of co-adsorbate is required. Gradually, a few times improvement of quantum efficiency was observed at sensitizer/co-adsorbate ratio Pc/CDCA = 1:10 and higher. The time-resolved spectroscopy studies were complemented by standard photocurrent measurements of the same sample structures, which also confirmed gradual increase in photon-to-current conversion efficiency on mixing Pc with CDCA K.V. acknowledges the Doctoral Programme of Tampere University of Technology for the financial support. N.V.T. acknowledges NATO SPS project no. 985043. Financial support from Comunidad de Madrid, Spain (S2013/MIT2841, FOTOCARBON) and MINECO, Spain (CTQ2014- 52869-P and CTQ2017-85393-P) is acknowledged. IMDEA Nanociencia acknowledges support from the “Severo Ochoa” Programme for Centres of Excellence in R&D (MINECO, grant SEV-2016-0686). |
| Databáze: | OpenAIRE |
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