Zr(IV) and Hf(IV) Porphyrinate complexes as Suitable dyes for Photovoltaic Devices

  • Alexander Falber, The University of Sydney, Australia
  • Allan Larsen, The University of Sydney, Australia
  • Prof Maxwell Crossley, School of Molecular and Microbial Biosciences, The University of Sydney, Australia
  • Charles Drain, The University of Sydney, Australia
  • Dr Udo Bach, Department of Materials Engineering, Monash University, Clayton, Victoria, 3800, Australia, Australia

    • As porphyrins play a critical role in photosynthesis, we continually strive to synthesise porphyrin complexes that can harvest incident light energy and effect charge transfer from photo-induced porphyrin excited states. Major goals in this field of work include 1. creation of large arrays of porphyrins over which charge separation can be stabilised and 2. harvest the charge within a photovoltaic device. Recently published work as well as our current work in Hf(IV) and Zr(IV) porphyrinate complexes offer a versatile template on the out-of-plane metal ion that easily binds to both organic and inorganic substrates bearing oxygen binding sites. We have observed dimer formation that may hold the key to more complex self-assembled porphyrin arrays. In particular we present Zr(IV) porphyrinates derivatives with extended ß-pyrrolic systems. Analogous free base and Zn(II) metallated systems have shown potential applications for photovoltaics. Crystal structures, cyclic voltammetry, and UV-Vis spectra of these various derivatives display new and interesting architectures of porphyrin systems.