title: Polymer/Nanocrystal Hybrid Solar Cells: Influence of Molecular Precursor Design on Film Nanomorphology, Charge Generation and Device Performance.
abstract: In this work, molecular tuning of metal xanthate precursors is shown to have a marked effect on the heterojunction morphology of hybrid poly(3-hexylthiophene-2,5-diyl) (P3HT)/CdS blends and, as a result, the photochemical processes and overall performance of in situ fabricated hybrid solar cells. A series of cadmium xanthate complexes is synthesized for use as in situ precursors to cadmium sulfide nanoparticles in hybrid P3HT/CdS solar cells. The formation of CdS domains is studied by simultaneous GIWAXS (grazing incidence wide-angle X-ray scattering) and GISAXS (grazing incidence small-angle X-ray scattering), revealing knowledge about crystal growth and the formation of different morphologies observed using TEM (transmission electron microscopy). These measurements show that there is a strong relationship between precursor structure and heterojunction nanomorphology. A combination of TAS (transient absorption spectroscopy) and photovoltaic device performance measurements is used to show the intricate balance required between charge photogeneration and percolated domains in order to effectively extract charges to maximize device power conversion efficiencies. This study presents a strong case for xanthate complexes as a useful route to designing optimal heterojunction morphologies for use in the emerging field of hybrid organic/inorganic solar cells, due to the fact that the nanomorphology can be tuned via careful design of these precursor materials.
authors: Department of Chemistry and Centre for Plastic Electronics, Imperial College London Imperial College Road, London, SW7 2AZ, UK.
authors: Andrew J
authors: AJ
authors: MacLachlan
authors: Department of Chemistry and Centre for Plastic Electronics, Imperial College London Imperial College Road, London, SW7 2AZ, UK.
authors: Thomas
authors: T
authors: Rath
authors: Department of Chemistry and Centre for Plastic Electronics, Imperial College London Imperial College Road, London, SW7 2AZ, UK.
authors: Ute B
authors: UB
authors: Cappel
authors: Department of Chemistry and Centre for Plastic Electronics, Imperial College London Imperial College Road, London, SW7 2AZ, UK.
authors: Simon A
authors: SA
authors: Dowland
authors: Institute for Inorganic Chemistry, NAWI Graz, Graz University of Technology Stremayrgasse 9, 8010, Graz, Austria.
authors: Heinz
authors: H
authors: Amenitsch
authors: Department of Chemistry and Centre for Plastic Electronics, Imperial College London Imperial College Road, London, SW7 2AZ, UK ; Institute for Chemistry and Technology of Materials, NAWI Graz, Graz University of Technology Stremayrgasse 9, 8010, Graz, Austria.
authors: Astrid-Caroline
authors: AC
authors: Knall
authors: Institute for Chemistry and Technology of Materials, NAWI Graz, Graz University of Technology Stremayrgasse 9, 8010, Graz, Austria.
authors: Christine
authors: C
authors: Buchmaier
authors: Institute for Chemistry and Technology of Materials, NAWI Graz, Graz University of Technology Stremayrgasse 9, 8010, Graz, Austria.
authors: Gregor
authors: G
authors: Trimmel
authors: Department of Physics and Centre for Plastic Electronics, Imperial College London Imperial College Road, London, SW7 2AZ, UK.
authors: Jenny
authors: J
authors: Nelson
authors: Department of Chemistry and Centre for Plastic Electronics, Imperial College London Imperial College Road, London, SW7 2AZ, UK.
authors: Saif A
authors: SA
authors: Haque
keywords: hybrid materials; organic electronics; photovoltaic devices; solar cells; spectroscopy