Structure–Function Relationships in Unsymmetrical Zinc Phthalocyanines for Dye-Sensitized Solar Cells

Authors

  • Juan-José Cid Dr.,

    1. Departamento de Química Orgánica, Universidad Autónoma de Madrid, Cantoblanco, 28049, Madrid (Spain), Fax: (+34) 914-973-966
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  • Miguel García-Iglesias,

    1. Departamento de Química Orgánica, Universidad Autónoma de Madrid, Cantoblanco, 28049, Madrid (Spain), Fax: (+34) 914-973-966
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  • Jun-Ho Yum Dr.,

    1. Laboratory for Photonics and Interfaces, Institute of Chemical Sciences and Engineering, School of Basic Sciences, Swiss Federal Institute of Technology, 1015 Lausanne (Switzerland), Fax: (+41) 216-934-111
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  • Amparo Forneli,

    1. Institute of Chemical Research of Catalonia, ICIQ, Avda. Països Catalans 16, 43007 Tarragona (Spain), Fax: (+34) 977-920-223
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  • Josep Albero,

    1. Institute of Chemical Research of Catalonia, ICIQ, Avda. Països Catalans 16, 43007 Tarragona (Spain), Fax: (+34) 977-920-223
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  • Eugenia Martínez-Ferrero Dr.,

    1. Institute of Chemical Research of Catalonia, ICIQ, Avda. Països Catalans 16, 43007 Tarragona (Spain), Fax: (+34) 977-920-223
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  • Purificación Vázquez Prof.,

    1. Departamento de Química Orgánica, Universidad Autónoma de Madrid, Cantoblanco, 28049, Madrid (Spain), Fax: (+34) 914-973-966
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  • Michael Grätzel Prof.,

    1. Laboratory for Photonics and Interfaces, Institute of Chemical Sciences and Engineering, School of Basic Sciences, Swiss Federal Institute of Technology, 1015 Lausanne (Switzerland), Fax: (+41) 216-934-111
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  • Mohammad K. Nazeeruddin Prof.,

    1. Laboratory for Photonics and Interfaces, Institute of Chemical Sciences and Engineering, School of Basic Sciences, Swiss Federal Institute of Technology, 1015 Lausanne (Switzerland), Fax: (+41) 216-934-111
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  • Emilio Palomares Prof.,

    1. Institute of Chemical Research of Catalonia, ICIQ, Avda. Països Catalans 16, 43007 Tarragona (Spain), Fax: (+34) 977-920-223
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  • Tomás Torres Prof.

    1. Departamento de Química Orgánica, Universidad Autónoma de Madrid, Cantoblanco, 28049, Madrid (Spain), Fax: (+34) 914-973-966
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Abstract

Let it shine! The impact of the anchoring group on photovoltaic performance by a series of phthalocyanine sensitisers (see figure) has been demonstrated.

original image

A series of unsymmetrical zinc phthalocyanines bearing an anchoring carboxylic function linked to the phthalocyanine ring through different spacers were designed for dye-sensitised solar cells (DSSC). The modification of the spacer group allows not only a variable distance between the dye and the nanocrystalline TiO2, but also a distinct orientation of the phthalocyanine on the semiconductor surface. The photovoltaic data show that the nature of the spacer group plays a significant role in the electron injection from the photo-excited dye into the nanocrystalline TiO2 semiconductor, the recombination rates and the efficiency of the cells. The incident monochromatic photon-to-current conversion efficiency (IPCE) for phthalocyanines bearing an insulating spacer is as low as 9 %, whereas for those with a conducting spacer an outstanding IPCE 80 % was obtained.

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