In situ radiotracer and voltammetric study of the formation of surface adlayers in the course of Cr(VI) reduction on polycrystalline and (1 1 1) oriented platinum

Renáta Buják, K. Varga

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

This paper is focused on the in situ radiotracer and voltammetric studies of the induced HSO4-/SO42- adsorption at Pt(poly) and Pt(1 1 1) surfaces in 0.1 mol dm-3 HClO4 solution in the course of Cr(VI) electroreduction. Besides this, the sorption behavior of HSO4-/SO42- ions on bare Pt(poly) and Pt(1 1 1) electrodes is compared and discussed. From the experimental results it can be stated that: (i) although the extent of bisulfate/sulfate adsorption is strongly dependent upon the crystallographic orientation of Pt surfaces, the maximum coverage on the Pt(1 1 1) does not exceed 0.2 monolayer; (ii) the Cr(VI) electroreduction on both poly- and (1 1 1) oriented platinum proceeds via a ce (chemical-electron-transfer) mechanism to yield Pt surfaces covered with intermediate surface adlayers containing Cr(VI) particles (and reduced Cr-containing adspecies) and 'strongly bonded' HSO4-/SO42- ions; (iii) while the coverage of platinum surfaces by the intermediate complexes formed in the course of Cr(VI) electroreduction at E > 0.20 V is basically independent of the crystallographic orientation of the Pt electrode, the onset for rapid Cr(VI) reduction is highly affected by the nature and crystallographic orientation of the electrode.

Original languageEnglish
Pages (from-to)332-341
Number of pages10
JournalElectrochimica Acta
Volume52
Issue number1
DOIs
Publication statusPublished - Oct 5 2006

Fingerprint

Platinum
Electrodes
Ions
Adsorption
Sulfates
Sorption
Monolayers
chromium hexavalent ion
Electrons

Keywords

  • Bisulfate adsorption
  • Cr(VI) reduction
  • In situ radiotracer 'thin gap' method
  • Pt(poly) and Pt(1 1 1)

ASJC Scopus subject areas

  • Chemical Engineering(all)
  • Analytical Chemistry
  • Electrochemistry

Cite this

@article{efd670abb9814738adea82edad1318e8,
title = "In situ radiotracer and voltammetric study of the formation of surface adlayers in the course of Cr(VI) reduction on polycrystalline and (1 1 1) oriented platinum",
abstract = "This paper is focused on the in situ radiotracer and voltammetric studies of the induced HSO4-/SO42- adsorption at Pt(poly) and Pt(1 1 1) surfaces in 0.1 mol dm-3 HClO4 solution in the course of Cr(VI) electroreduction. Besides this, the sorption behavior of HSO4-/SO42- ions on bare Pt(poly) and Pt(1 1 1) electrodes is compared and discussed. From the experimental results it can be stated that: (i) although the extent of bisulfate/sulfate adsorption is strongly dependent upon the crystallographic orientation of Pt surfaces, the maximum coverage on the Pt(1 1 1) does not exceed 0.2 monolayer; (ii) the Cr(VI) electroreduction on both poly- and (1 1 1) oriented platinum proceeds via a ce (chemical-electron-transfer) mechanism to yield Pt surfaces covered with intermediate surface adlayers containing Cr(VI) particles (and reduced Cr-containing adspecies) and 'strongly bonded' HSO4-/SO42- ions; (iii) while the coverage of platinum surfaces by the intermediate complexes formed in the course of Cr(VI) electroreduction at E > 0.20 V is basically independent of the crystallographic orientation of the Pt electrode, the onset for rapid Cr(VI) reduction is highly affected by the nature and crystallographic orientation of the electrode.",
keywords = "Bisulfate adsorption, Cr(VI) reduction, In situ radiotracer 'thin gap' method, Pt(poly) and Pt(1 1 1)",
author = "Ren{\'a}ta Buj{\'a}k and K. Varga",
year = "2006",
month = "10",
day = "5",
doi = "10.1016/j.electacta.2006.05.012",
language = "English",
volume = "52",
pages = "332--341",
journal = "Electrochimica Acta",
issn = "0013-4686",
publisher = "Elsevier Limited",
number = "1",

}

TY - JOUR

T1 - In situ radiotracer and voltammetric study of the formation of surface adlayers in the course of Cr(VI) reduction on polycrystalline and (1 1 1) oriented platinum

AU - Buják, Renáta

AU - Varga, K.

PY - 2006/10/5

Y1 - 2006/10/5

N2 - This paper is focused on the in situ radiotracer and voltammetric studies of the induced HSO4-/SO42- adsorption at Pt(poly) and Pt(1 1 1) surfaces in 0.1 mol dm-3 HClO4 solution in the course of Cr(VI) electroreduction. Besides this, the sorption behavior of HSO4-/SO42- ions on bare Pt(poly) and Pt(1 1 1) electrodes is compared and discussed. From the experimental results it can be stated that: (i) although the extent of bisulfate/sulfate adsorption is strongly dependent upon the crystallographic orientation of Pt surfaces, the maximum coverage on the Pt(1 1 1) does not exceed 0.2 monolayer; (ii) the Cr(VI) electroreduction on both poly- and (1 1 1) oriented platinum proceeds via a ce (chemical-electron-transfer) mechanism to yield Pt surfaces covered with intermediate surface adlayers containing Cr(VI) particles (and reduced Cr-containing adspecies) and 'strongly bonded' HSO4-/SO42- ions; (iii) while the coverage of platinum surfaces by the intermediate complexes formed in the course of Cr(VI) electroreduction at E > 0.20 V is basically independent of the crystallographic orientation of the Pt electrode, the onset for rapid Cr(VI) reduction is highly affected by the nature and crystallographic orientation of the electrode.

AB - This paper is focused on the in situ radiotracer and voltammetric studies of the induced HSO4-/SO42- adsorption at Pt(poly) and Pt(1 1 1) surfaces in 0.1 mol dm-3 HClO4 solution in the course of Cr(VI) electroreduction. Besides this, the sorption behavior of HSO4-/SO42- ions on bare Pt(poly) and Pt(1 1 1) electrodes is compared and discussed. From the experimental results it can be stated that: (i) although the extent of bisulfate/sulfate adsorption is strongly dependent upon the crystallographic orientation of Pt surfaces, the maximum coverage on the Pt(1 1 1) does not exceed 0.2 monolayer; (ii) the Cr(VI) electroreduction on both poly- and (1 1 1) oriented platinum proceeds via a ce (chemical-electron-transfer) mechanism to yield Pt surfaces covered with intermediate surface adlayers containing Cr(VI) particles (and reduced Cr-containing adspecies) and 'strongly bonded' HSO4-/SO42- ions; (iii) while the coverage of platinum surfaces by the intermediate complexes formed in the course of Cr(VI) electroreduction at E > 0.20 V is basically independent of the crystallographic orientation of the Pt electrode, the onset for rapid Cr(VI) reduction is highly affected by the nature and crystallographic orientation of the electrode.

KW - Bisulfate adsorption

KW - Cr(VI) reduction

KW - In situ radiotracer 'thin gap' method

KW - Pt(poly) and Pt(1 1 1)

UR - http://www.scopus.com/inward/record.url?scp=33748565911&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=33748565911&partnerID=8YFLogxK

U2 - 10.1016/j.electacta.2006.05.012

DO - 10.1016/j.electacta.2006.05.012

M3 - Article

AN - SCOPUS:33748565911

VL - 52

SP - 332

EP - 341

JO - Electrochimica Acta

JF - Electrochimica Acta

SN - 0013-4686

IS - 1

ER -