Fast hole surface conduction observed for indoline sensitizer dyes immobilized at fluorine-doped tin oxide-TiO2 surfaces

Alberto Fattori, Laurence M Peter, H X Wang, H Miura, Frank Marken

Research output: Contribution to journalArticle

  • 35 Citations

Abstract

The indoline dyes D102, D131, D149, and D205 have been characterized when adsorbed on fluorine-doped tin oxide (FTO) and TiO2 electrode surfaces. Adsorption from 50:50 acetonitrile tert-butanol onto fluorine-doped tin oxide (FTO) allows approximate Langmuirian binding constants of 6.5 x 10(4), 2.0 x 10(3), 2.0 x 10(4), and 1.5 x 10(4) mol(-1) dm(3), respectively, to be determined. Voltammetric data obtained in acetonitrile/0.1 M NBu4PF6 indicate reversible one-electron oxidation at E-mid = 0.94, 0.91, 0.88, and 0.88 V vs Ag/AgCl(3 M KCl), respectively, with dye aggregation (at high coverage) causing additional peak features at more positive potentials. Slow chemical degradation processes and electron transfer catalysis for iodide oxidation were observed for all four oxidized indolinium cations. When adsorbed onto TiO2 nanoparticle films (ca. 9 nm particle diameter and ca. 3 mu m thickness on FTO), reversible voltammetric responses with E-mid = 1.08, 1.16, 0.92, and 0.95 V vs Ag/AgCl(3 M KCl), respectively, suggest exceptionally fast hole hopping diffusion (with D-app > 5 x 10(-9) m(2) s(-1)) for adsorbed layers of all four indoline dyes, presumably due to pi-pi stacking in surface aggregates. Slow dye degradation is shown to affect charge transport via electron hopping. Spectroelectrochemical data for the adsorbed indoline dyes on FTO-TiO2 revealed a red-shift of absorption peaks after oxidation and the presence of a strong charge transfer band in the near-IR region. The implications of the indoline dye reactivity and fast hole mobility for solar cell devices are discussed.
LanguageEnglish
Pages11822-11828
Number of pages7
JournalJournal of Physical Chemistry C
Volume114
Issue number27
DOIs
StatusPublished - 15 Jul 2010

Fingerprint

Fluorine
Tin oxides
tin oxides
fluorine
Coloring Agents
Dyes
dyes
conduction
Acetonitrile
Oxidation
oxidation
acetonitrile
Electrons
Charge transfer
tert-Butyl Alcohol
degradation
Degradation
Hole mobility
hole mobility
Iodides

Cite this

Fast hole surface conduction observed for indoline sensitizer dyes immobilized at fluorine-doped tin oxide-TiO2 surfaces. / Fattori, Alberto; Peter, Laurence M; Wang, H X; Miura, H; Marken, Frank.

In: Journal of Physical Chemistry C, Vol. 114, No. 27, 15.07.2010, p. 11822-11828.

Research output: Contribution to journalArticle

@article{45774cb7c7d74503badc845e3ce47ee4,
title = "Fast hole surface conduction observed for indoline sensitizer dyes immobilized at fluorine-doped tin oxide-TiO2 surfaces",
abstract = "The indoline dyes D102, D131, D149, and D205 have been characterized when adsorbed on fluorine-doped tin oxide (FTO) and TiO2 electrode surfaces. Adsorption from 50:50 acetonitrile tert-butanol onto fluorine-doped tin oxide (FTO) allows approximate Langmuirian binding constants of 6.5 x 10(4), 2.0 x 10(3), 2.0 x 10(4), and 1.5 x 10(4) mol(-1) dm(3), respectively, to be determined. Voltammetric data obtained in acetonitrile/0.1 M NBu4PF6 indicate reversible one-electron oxidation at E-mid = 0.94, 0.91, 0.88, and 0.88 V vs Ag/AgCl(3 M KCl), respectively, with dye aggregation (at high coverage) causing additional peak features at more positive potentials. Slow chemical degradation processes and electron transfer catalysis for iodide oxidation were observed for all four oxidized indolinium cations. When adsorbed onto TiO2 nanoparticle films (ca. 9 nm particle diameter and ca. 3 mu m thickness on FTO), reversible voltammetric responses with E-mid = 1.08, 1.16, 0.92, and 0.95 V vs Ag/AgCl(3 M KCl), respectively, suggest exceptionally fast hole hopping diffusion (with D-app > 5 x 10(-9) m(2) s(-1)) for adsorbed layers of all four indoline dyes, presumably due to pi-pi stacking in surface aggregates. Slow dye degradation is shown to affect charge transport via electron hopping. Spectroelectrochemical data for the adsorbed indoline dyes on FTO-TiO2 revealed a red-shift of absorption peaks after oxidation and the presence of a strong charge transfer band in the near-IR region. The implications of the indoline dye reactivity and fast hole mobility for solar cell devices are discussed.",
author = "Alberto Fattori and Peter, {Laurence M} and Wang, {H X} and H Miura and Frank Marken",
year = "2010",
month = "7",
day = "15",
doi = "10.1021/jp103808u",
language = "English",
volume = "114",
pages = "11822--11828",
journal = "Journal of Physical Chemistry C",
issn = "1932-7447",
publisher = "American Chemical Society",
number = "27",

}

TY - JOUR

T1 - Fast hole surface conduction observed for indoline sensitizer dyes immobilized at fluorine-doped tin oxide-TiO2 surfaces

AU - Fattori,Alberto

AU - Peter,Laurence M

AU - Wang,H X

AU - Miura,H

AU - Marken,Frank

PY - 2010/7/15

Y1 - 2010/7/15

N2 - The indoline dyes D102, D131, D149, and D205 have been characterized when adsorbed on fluorine-doped tin oxide (FTO) and TiO2 electrode surfaces. Adsorption from 50:50 acetonitrile tert-butanol onto fluorine-doped tin oxide (FTO) allows approximate Langmuirian binding constants of 6.5 x 10(4), 2.0 x 10(3), 2.0 x 10(4), and 1.5 x 10(4) mol(-1) dm(3), respectively, to be determined. Voltammetric data obtained in acetonitrile/0.1 M NBu4PF6 indicate reversible one-electron oxidation at E-mid = 0.94, 0.91, 0.88, and 0.88 V vs Ag/AgCl(3 M KCl), respectively, with dye aggregation (at high coverage) causing additional peak features at more positive potentials. Slow chemical degradation processes and electron transfer catalysis for iodide oxidation were observed for all four oxidized indolinium cations. When adsorbed onto TiO2 nanoparticle films (ca. 9 nm particle diameter and ca. 3 mu m thickness on FTO), reversible voltammetric responses with E-mid = 1.08, 1.16, 0.92, and 0.95 V vs Ag/AgCl(3 M KCl), respectively, suggest exceptionally fast hole hopping diffusion (with D-app > 5 x 10(-9) m(2) s(-1)) for adsorbed layers of all four indoline dyes, presumably due to pi-pi stacking in surface aggregates. Slow dye degradation is shown to affect charge transport via electron hopping. Spectroelectrochemical data for the adsorbed indoline dyes on FTO-TiO2 revealed a red-shift of absorption peaks after oxidation and the presence of a strong charge transfer band in the near-IR region. The implications of the indoline dye reactivity and fast hole mobility for solar cell devices are discussed.

AB - The indoline dyes D102, D131, D149, and D205 have been characterized when adsorbed on fluorine-doped tin oxide (FTO) and TiO2 electrode surfaces. Adsorption from 50:50 acetonitrile tert-butanol onto fluorine-doped tin oxide (FTO) allows approximate Langmuirian binding constants of 6.5 x 10(4), 2.0 x 10(3), 2.0 x 10(4), and 1.5 x 10(4) mol(-1) dm(3), respectively, to be determined. Voltammetric data obtained in acetonitrile/0.1 M NBu4PF6 indicate reversible one-electron oxidation at E-mid = 0.94, 0.91, 0.88, and 0.88 V vs Ag/AgCl(3 M KCl), respectively, with dye aggregation (at high coverage) causing additional peak features at more positive potentials. Slow chemical degradation processes and electron transfer catalysis for iodide oxidation were observed for all four oxidized indolinium cations. When adsorbed onto TiO2 nanoparticle films (ca. 9 nm particle diameter and ca. 3 mu m thickness on FTO), reversible voltammetric responses with E-mid = 1.08, 1.16, 0.92, and 0.95 V vs Ag/AgCl(3 M KCl), respectively, suggest exceptionally fast hole hopping diffusion (with D-app > 5 x 10(-9) m(2) s(-1)) for adsorbed layers of all four indoline dyes, presumably due to pi-pi stacking in surface aggregates. Slow dye degradation is shown to affect charge transport via electron hopping. Spectroelectrochemical data for the adsorbed indoline dyes on FTO-TiO2 revealed a red-shift of absorption peaks after oxidation and the presence of a strong charge transfer band in the near-IR region. The implications of the indoline dye reactivity and fast hole mobility for solar cell devices are discussed.

UR - http://www.scopus.com/inward/record.url?scp=77955339506&partnerID=8YFLogxK

UR - http://dx.doi.org/10.1021/jp103808u

U2 - 10.1021/jp103808u

DO - 10.1021/jp103808u

M3 - Article

VL - 114

SP - 11822

EP - 11828

JO - Journal of Physical Chemistry C

T2 - Journal of Physical Chemistry C

JF - Journal of Physical Chemistry C

SN - 1932-7447

IS - 27

ER -