Platinum-like Behavior of Reduced Graphene Oxide as a Cocatalyst on TiO 2 for the Efficient Photocatalytic Oxidation of Arsenite

Gun Hee Moon, Dong Hyo Kim, Hyoung Il Kim, Alok D. Bokare, Wonyong Choi

Research output: Contribution to journalArticle

71 Citations (Scopus)

Abstract

The preoxidation of arsenite [As(III)] to arsenate [As(V)] is usually needed for efficient removal of arsenic from water, and TiO 2 -based photocatalytic oxidation has been investigated as an environmentally benign process for this purpose. The oxidation efficiency can be markedly enhanced when using platinum (Pt) as a cocatalyst, but its expensive material cost hinders its practical application. Herein, we prepared the reduced graphene oxide (rGO) hybridized with TiO 2 as a low-cost alternative to Pt and achieved a highly enhanced activity for the photocatalytic oxidation of As(III), which is comparable to that of Pt/TiO 2 . While either superoxide or hydroxyl radical can be involved as a main oxidant depending on the experimental condition, this study shows that not only superoxide but also hydroxyl radicals (or hole) can be directly involved in As(III) photo-oxidation when rGO is present as a cocatalyst. The photocatalytic activity, charge transfer characteristics, and arsenic oxidation mechanism observed with rGO-loaded TiO 2 are very similar to those of Pt/TiO 2 . The nanocomposite of rGO/TiO 2 that consists of earth-abundant elements only is proposed as a practical environmental photocatalyst for pretreating As(III)-contaminated water.

Original languageEnglish
Pages (from-to)185-190
Number of pages6
JournalEnvironmental Science and Technology Letters
Volume1
Issue number2
DOIs
Publication statusPublished - 2014 Feb 11

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Graphite
arsenite
Platinum
platinum
Oxides
Graphene
oxide
oxidation
Oxidation
Arsenic
hydroxyl radical
Superoxides
Hydroxyl Radical
arsenic
Nanocomposites
Costs and Cost Analysis
Photooxidation
Water
photooxidation
arsenate

All Science Journal Classification (ASJC) codes

  • Environmental Chemistry
  • Ecology
  • Water Science and Technology
  • Waste Management and Disposal
  • Pollution
  • Health, Toxicology and Mutagenesis

Cite this

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abstract = "The preoxidation of arsenite [As(III)] to arsenate [As(V)] is usually needed for efficient removal of arsenic from water, and TiO 2 -based photocatalytic oxidation has been investigated as an environmentally benign process for this purpose. The oxidation efficiency can be markedly enhanced when using platinum (Pt) as a cocatalyst, but its expensive material cost hinders its practical application. Herein, we prepared the reduced graphene oxide (rGO) hybridized with TiO 2 as a low-cost alternative to Pt and achieved a highly enhanced activity for the photocatalytic oxidation of As(III), which is comparable to that of Pt/TiO 2 . While either superoxide or hydroxyl radical can be involved as a main oxidant depending on the experimental condition, this study shows that not only superoxide but also hydroxyl radicals (or hole) can be directly involved in As(III) photo-oxidation when rGO is present as a cocatalyst. The photocatalytic activity, charge transfer characteristics, and arsenic oxidation mechanism observed with rGO-loaded TiO 2 are very similar to those of Pt/TiO 2 . The nanocomposite of rGO/TiO 2 that consists of earth-abundant elements only is proposed as a practical environmental photocatalyst for pretreating As(III)-contaminated water.",
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Platinum-like Behavior of Reduced Graphene Oxide as a Cocatalyst on TiO 2 for the Efficient Photocatalytic Oxidation of Arsenite . / Moon, Gun Hee; Kim, Dong Hyo; Kim, Hyoung Il; Bokare, Alok D.; Choi, Wonyong.

In: Environmental Science and Technology Letters, Vol. 1, No. 2, 11.02.2014, p. 185-190.

Research output: Contribution to journalArticle

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