Immobilisation of electroactive macrocyclic complexes within titania films

Abstract

The 4-carboxyphenyl-appended macrocyclic ligand trans-6,13-dimethyl-6-((4-carboxybenzyl) 2− was also prepared and chemisorbed on titania-coated ITO conducting glass. The adsorbed complex is electrochemically active and cyclic voltammetry of the modified ITO working electrode in both water and MeCN solution was undertaken with simultaneous optical spectroscopy. This experiment demonstrates that reversible electrochemical oxidation of the Fe II centre is coupled with rapid changes in the optical absorbance of the film.

Tailoring mixed-valence CoIII/FeII complexes for their potential use as sensitizers in dye sensitized solar cells

“…The nature of the isomerism of the macrocycle around the cobalt centre is established by the number of signals in the 13 C NMR spectrum. These indicate that the structure is fully symmetric with only six types of non-carboxylic carbons, which corresponds to a trans-I or trans-III macrocycle isomeric form, 19 as defined for cyclam complexes.…”

“…A few drops of concentrated HClO 4 were added and the product was left to crystallize by slow evaporation in a 18% yield. 13 C NMR (100 MHz, D 2 O, 298 K), d/ppm: 30.0, 50.8, 53.8, 55.6, 57.4, 61.4, 183.8. UV-Vis, l max /nm: 376, 536; e 376 /e 536 = 1.54.…”

“…150 cm 3 of cold EtOH was added and the precipitate in a 11% yield was dried in air. 13 /mV: À330, 610. Elemental analysis indicated a C : N ratio of 1.67 in good agreement with the presence of six cyanide ligands and the L 14COO macrocyclic ligand in the complex (C : N = 1.64).…”

“…NMR spectra were recorded on a Varian Mercury-400 ( 1 H, 400 MHz or 13 C 100.6 MHz) instrument in D 2 O and using NaTSP as external standard at the Serveis Cientı´fico-Te`cnics of the Universitat de Barcelona. Elemental analyses were carried out also by the Serveis Cientı´fico-Te`cnics of the Universitat de Barcelona.…”

“…12 In fact, some developments on this area with implications on smart windows have already been published. 13 In this paper we present the intended use of two new tailormade dinuclear Co III /Fe II mixed valence complexes (Scheme 1) designed to ensure the possibility of two different electron injection pathways from the molecule to the mesoporous oxide semiconducting electrode of an DSSC. 14,15 The relative orientation of these metal dyads, as a key point for the electron injection, has also been looked into.…”