Novel Pt Electrocatalysts: Multifunctional Composite Supports for Enhanced Corrosion Resistance and Improved CO Tolerance

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

The electrochemical peculiarities of novel 20 wt% Pt electrocatalysts supported on Ti0.6Mo0.4O2–C composite materials in low-potential CO oxidation reaction (LPCOR) were investigated. The oxidation of CO on the Mo-containing Pt-based catalyst commences at exceptionally low potential values (ca. 100 mV). The results suggest that only CO adsorbed on specific Pt sites, where Pt and Mo atoms are in atomic closeness, can be oxidised below 400 mV potential. When the weakly bounded CO is oxidized, some hydrogen adsorption can take place on the released surface, although this amount is much smaller than in the case of a CO-free Pt surface. The Pt/Ti0.6Mo0.4O2–C catalyst loses its activity in LPCOR when Mo becomes oxidized (above ca. 400 mV). Accordingly, presence of Mo species in lower oxidation state than 6+ is supposed to have crucial role in CO oxidation. Nevertheless, re-reduction of oxidized Mo species formed above 400 mV is strongly hindered when adsorbed CO species are still present. Note that COads species can be completely removed only above 550 mV. Oxidized Mo species can be re-reduced and the activity in the LPCOR can be restored if the platinum surface is CO-free. Clear correlation between the so-called “pre-peak”, the molybdenum redox phenomenon and the CO tolerance of the 20 wt% Pt/Ti0.6Mo0.4O2–C system was established. Better performance of the Pt/Ti0.6Mo0.4O2–C electrocatalyst compared to commercially available reference Pt/C and state-of-art CO-tolerant PtRu/C (Quintech) catalysts was also demonstrated.

Original languageEnglish
Pages (from-to)1-13
Number of pages13
JournalTopics in Catalysis
DOIs
Publication statusAccepted/In press - May 11 2018

Fingerprint

Electrocatalysts
Carbon Monoxide
Catalyst supports
Corrosion resistance
Oxidation
Composite materials
Catalysts
Molybdenum
Platinum
Adsorption
Atoms
Hydrogen

Keywords

  • CO-tolerance
  • Composite materials
  • Conducting Ti-based mixed oxides
  • Pt electrocatalysts
  • TiMoO

ASJC Scopus subject areas

  • Catalysis
  • Chemistry(all)

Cite this

@article{4d33fa427c4b40589802b3081b9c4c54,
title = "Novel Pt Electrocatalysts: Multifunctional Composite Supports for Enhanced Corrosion Resistance and Improved CO Tolerance",
abstract = "The electrochemical peculiarities of novel 20 wt{\%} Pt electrocatalysts supported on Ti0.6Mo0.4O2–C composite materials in low-potential CO oxidation reaction (LPCOR) were investigated. The oxidation of CO on the Mo-containing Pt-based catalyst commences at exceptionally low potential values (ca. 100 mV). The results suggest that only CO adsorbed on specific Pt sites, where Pt and Mo atoms are in atomic closeness, can be oxidised below 400 mV potential. When the weakly bounded CO is oxidized, some hydrogen adsorption can take place on the released surface, although this amount is much smaller than in the case of a CO-free Pt surface. The Pt/Ti0.6Mo0.4O2–C catalyst loses its activity in LPCOR when Mo becomes oxidized (above ca. 400 mV). Accordingly, presence of Mo species in lower oxidation state than 6+ is supposed to have crucial role in CO oxidation. Nevertheless, re-reduction of oxidized Mo species formed above 400 mV is strongly hindered when adsorbed CO species are still present. Note that COads species can be completely removed only above 550 mV. Oxidized Mo species can be re-reduced and the activity in the LPCOR can be restored if the platinum surface is CO-free. Clear correlation between the so-called “pre-peak”, the molybdenum redox phenomenon and the CO tolerance of the 20 wt{\%} Pt/Ti0.6Mo0.4O2–C system was established. Better performance of the Pt/Ti0.6Mo0.4O2–C electrocatalyst compared to commercially available reference Pt/C and state-of-art CO-tolerant PtRu/C (Quintech) catalysts was also demonstrated.",
keywords = "CO-tolerance, Composite materials, Conducting Ti-based mixed oxides, Pt electrocatalysts, TiMoO",
author = "Vass and I. Borb{\'a}th and I. Bakos and Z. P{\'a}szti and I. Saj{\'o} and A. Tompos",
year = "2018",
month = "5",
day = "11",
doi = "10.1007/s11244-018-0988-0",
language = "English",
pages = "1--13",
journal = "Topics in Catalysis",
issn = "1022-5528",
publisher = "Springer Netherlands",

}

TY - JOUR

T1 - Novel Pt Electrocatalysts

T2 - Multifunctional Composite Supports for Enhanced Corrosion Resistance and Improved CO Tolerance

AU - Vass,

AU - Borbáth, I.

AU - Bakos, I.

AU - Pászti, Z.

AU - Sajó, I.

AU - Tompos, A.

PY - 2018/5/11

Y1 - 2018/5/11

N2 - The electrochemical peculiarities of novel 20 wt% Pt electrocatalysts supported on Ti0.6Mo0.4O2–C composite materials in low-potential CO oxidation reaction (LPCOR) were investigated. The oxidation of CO on the Mo-containing Pt-based catalyst commences at exceptionally low potential values (ca. 100 mV). The results suggest that only CO adsorbed on specific Pt sites, where Pt and Mo atoms are in atomic closeness, can be oxidised below 400 mV potential. When the weakly bounded CO is oxidized, some hydrogen adsorption can take place on the released surface, although this amount is much smaller than in the case of a CO-free Pt surface. The Pt/Ti0.6Mo0.4O2–C catalyst loses its activity in LPCOR when Mo becomes oxidized (above ca. 400 mV). Accordingly, presence of Mo species in lower oxidation state than 6+ is supposed to have crucial role in CO oxidation. Nevertheless, re-reduction of oxidized Mo species formed above 400 mV is strongly hindered when adsorbed CO species are still present. Note that COads species can be completely removed only above 550 mV. Oxidized Mo species can be re-reduced and the activity in the LPCOR can be restored if the platinum surface is CO-free. Clear correlation between the so-called “pre-peak”, the molybdenum redox phenomenon and the CO tolerance of the 20 wt% Pt/Ti0.6Mo0.4O2–C system was established. Better performance of the Pt/Ti0.6Mo0.4O2–C electrocatalyst compared to commercially available reference Pt/C and state-of-art CO-tolerant PtRu/C (Quintech) catalysts was also demonstrated.

AB - The electrochemical peculiarities of novel 20 wt% Pt electrocatalysts supported on Ti0.6Mo0.4O2–C composite materials in low-potential CO oxidation reaction (LPCOR) were investigated. The oxidation of CO on the Mo-containing Pt-based catalyst commences at exceptionally low potential values (ca. 100 mV). The results suggest that only CO adsorbed on specific Pt sites, where Pt and Mo atoms are in atomic closeness, can be oxidised below 400 mV potential. When the weakly bounded CO is oxidized, some hydrogen adsorption can take place on the released surface, although this amount is much smaller than in the case of a CO-free Pt surface. The Pt/Ti0.6Mo0.4O2–C catalyst loses its activity in LPCOR when Mo becomes oxidized (above ca. 400 mV). Accordingly, presence of Mo species in lower oxidation state than 6+ is supposed to have crucial role in CO oxidation. Nevertheless, re-reduction of oxidized Mo species formed above 400 mV is strongly hindered when adsorbed CO species are still present. Note that COads species can be completely removed only above 550 mV. Oxidized Mo species can be re-reduced and the activity in the LPCOR can be restored if the platinum surface is CO-free. Clear correlation between the so-called “pre-peak”, the molybdenum redox phenomenon and the CO tolerance of the 20 wt% Pt/Ti0.6Mo0.4O2–C system was established. Better performance of the Pt/Ti0.6Mo0.4O2–C electrocatalyst compared to commercially available reference Pt/C and state-of-art CO-tolerant PtRu/C (Quintech) catalysts was also demonstrated.

KW - CO-tolerance

KW - Composite materials

KW - Conducting Ti-based mixed oxides

KW - Pt electrocatalysts

KW - TiMoO

UR - http://www.scopus.com/inward/record.url?scp=85046763496&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85046763496&partnerID=8YFLogxK

U2 - 10.1007/s11244-018-0988-0

DO - 10.1007/s11244-018-0988-0

M3 - Article

AN - SCOPUS:85046763496

SP - 1

EP - 13

JO - Topics in Catalysis

JF - Topics in Catalysis

SN - 1022-5528

ER -