Functionalized alkynylplatinum(II) polypyridyl complexes for use as sensitizers in dye-sensitized solar cells

Abstract

A series of platinum(II) alkynyl-based sensitizers has been synthesized and found to show light-to-electricity conversion properties. These dyes were developed as sensitizers for the application in nanocrystalline TiO 2 dye-sensitized solar cells (DSSCs). Their photophysical and electrochemical properties were studied. The excited-state property was probed using nanosecond transient absorption spectroscopy, which showed the formation of a charge-separated state that arises from the intramolecular photoinduced charge transfer from the platinum(II) alkynylbithienylbenzothiadiazole moiety (donor) to the polypyridyl ligand (acceptor). A lifetime of 3.4 μs was observed for the charge-separated state. A dye-sensitized solar cell based on one of the complexes showed a short-circuit photocurrent of 7.12 mAcm -2, an open circuit voltage of 780 mV, and a fill factor of 0.65, thus giving an overall power conversion efficiency of 3.6%. Electric company: A series of platinum(II) alkynyl-based sensitizers has been synthesized and found to show light-to-electricity conversion properties (see graphic). A dye-sensitized solar cell based on one of the complexes shows a fill factor of 0.65 and a power-conversion efficiency of 3.6%. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.