title: Phosphonic acid functionalized asymmetric phthalocyanines: synthesis, modification of indium tin oxide, and charge transfer.
abstract: Metalated and free-base A(3)B-type asymmetric phthalocyanines (Pcs) bearing, in the asymmetric quadrant, a flexible alkyl linker of varying chain lengths terminating in a phosphonic acid (PA) group have been synthesized. Two parallel series of asymmetric Pc derivatives bearing aryloxy and arylthio substituents are reported, and their synthesis and characterization through NMR, combustion analysis, and MALDI-MS are described. We also demonstrate the modification of indium tin oxide (ITO) substrates using the PA functionalized asymmetric Pc derivatives and monitoring their electrochemistry. The PA functionalized asymmetric Pcs were anchored to the ITO surface through chemisorption and their electrochemical properties characterized using cyclic voltammetry to investigate the effects of PA structure on the thermodynamics and kinetics of charge transfer. Ionization energies of the modified ITO surfaces were measured using ultraviolet photoemission spectroscopy.
authors: Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85721, USA.
authors: Nathan W
authors: NW
authors: Polaske
authors: Hsiao-Chu
authors: HC
authors: Lin
authors: Anna
authors: A
authors: Tang
authors: Mayunk
authors: M
authors: Mayukh
authors: Luis E
authors: LE
authors: Oquendo
authors: John T
authors: JT
authors: Green
authors: Erin L
authors: EL
authors: Ratcliff
authors: Neal R
authors: NR
authors: Armstrong
authors: S Scott
authors: SS
authors: Saavedra
authors: Dominic V
authors: DV
authors: McGrath