DFT Study of bis(1, 10-phenanthroline)copper complexes: Molecular and electronic structure, redox and spectroscopic properties and application to Solar Cells. (20th June 2022)

• Record Type: Journal Article
• Authors: Conradie, Jeanet
• Is Part Of: Electrochimica acta. Volume 418(2022)
• Publication Date: 2022-06-20
• Subjects: Copper -- UV/vis -- Redox mediator -- Dye sensitizer -- DFT -- DSSC; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2022.140276
• Languages: English
• ISSNs: 0013-4686

Abstract

Highlights: Cu(II) complexes show promising properties for use as dye sensitizer for DSSCs. Cu(II) complexes with the required redox potential for use as redox mediator for DSSCs. Linear redox potential - DFT energies relationship enable design of redox mediators. Abstract: A density functional theory study (DFT) on the geometry, electronic structure and properties of a series of [Cu(phen)2 ] n + complexes ( n = 1 and 2, and phen = differently substituted phenanthroline ligands), is presented. The DFT study determined various properties of the complexes to be used either as dyes or as redox mediators in dye-sensitized solar cells (DSSCs). The calculated properties, namely absorption wavelength, light harvesting efficiency, excited state lifetime and driving force for electron injection, and the regeneration of these complexes, are favourable for these complexes to be used as dyes in DSSCs. However, the calculated electron transfer distance is small, implying excitation would result in a serious intramolecular electron recombination and low efficiency electron injection into the semiconductor. The redox properties of these complexes compare well with the redox reaction of the iodide/triiodide ( I − /I3 − ) redox mediator which is generally being used in DSSCs. Relationships obtained between experimental redox potentials and DFT calculated energies can be used to design and fine-tune complexes with a desired redox potential, as required for a redox mediator in DSSCs. Graphical abstract: Image, graphical abstract