Associating low crystallinity with peroxo groups for enhanced visible light active photocatalysts

Tamás Gyulavári, Gábor Veréb, Zsolt Pap, A. Dombi, K. Hernádi

Research output: Contribution to journalArticle

Abstract

In the present study hydrogen peroxide was applied during the synthesis of titanium dioxide (TiO2) photocatalysts to anchor peroxo groups onto the surface to enhance visible light excitability. The effect of changes in the pH value and crystallization temperature was investigated. As-prepared peroxo-titania were characterized by X-ray diffraction (XRD), diffuse reflectance spectroscopy (DRS), infrared spectroscopy (IR), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). The photocatalytic activity was investigated using phenol as model contaminant under visible light irradiation. IR and XPS measurements confirmed the presence of peroxo groups in the samples, moreover Raman and XPS measurements showed the formation of amorphous sodium titanate. Photocatalytic activity measurements pointed out, that most efficient as-prepared photocatalyst exceeded the photocatalytic performance of all reference materials. The cause of the enhanced photocatalytic activity was attributed to the enhanced visible light excitability and considerable amount of peroxo groups, which were not stable after the reusability experiments of the photocatalysts, suffering a redox reaction with the relatively high amount of Ti3+, resulting Ti4+ and surface OH groups. Therefore, the loss of peroxo groups and concomitantly photocatalytic activity was observed.

Original languageEnglish
JournalCatalysis Today
DOIs
Publication statusAccepted/In press - Jan 1 2018

Fingerprint

Photocatalysts
X ray photoelectron spectroscopy
Infrared spectroscopy
Redox reactions
Reusability
Crystallization
Phenol
Anchors
Hydrogen peroxide
Titanium dioxide
Hydrogen Peroxide
Phenols
Raman spectroscopy
Titanium
Sodium
Irradiation
Spectroscopy
Impurities
X ray diffraction
Experiments

Keywords

  • Peroxo group
  • Phenol
  • Sodium titanate
  • Titanium dioxide
  • Visible light

ASJC Scopus subject areas

  • Catalysis
  • Chemistry(all)

Cite this

Associating low crystallinity with peroxo groups for enhanced visible light active photocatalysts. / Gyulavári, Tamás; Veréb, Gábor; Pap, Zsolt; Dombi, A.; Hernádi, K.

In: Catalysis Today, 01.01.2018.

Research output: Contribution to journalArticle

@article{ec97390cd7e540a19089995dabe5d9af,
title = "Associating low crystallinity with peroxo groups for enhanced visible light active photocatalysts",
abstract = "In the present study hydrogen peroxide was applied during the synthesis of titanium dioxide (TiO2) photocatalysts to anchor peroxo groups onto the surface to enhance visible light excitability. The effect of changes in the pH value and crystallization temperature was investigated. As-prepared peroxo-titania were characterized by X-ray diffraction (XRD), diffuse reflectance spectroscopy (DRS), infrared spectroscopy (IR), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). The photocatalytic activity was investigated using phenol as model contaminant under visible light irradiation. IR and XPS measurements confirmed the presence of peroxo groups in the samples, moreover Raman and XPS measurements showed the formation of amorphous sodium titanate. Photocatalytic activity measurements pointed out, that most efficient as-prepared photocatalyst exceeded the photocatalytic performance of all reference materials. The cause of the enhanced photocatalytic activity was attributed to the enhanced visible light excitability and considerable amount of peroxo groups, which were not stable after the reusability experiments of the photocatalysts, suffering a redox reaction with the relatively high amount of Ti3+, resulting Ti4+ and surface OH groups. Therefore, the loss of peroxo groups and concomitantly photocatalytic activity was observed.",
keywords = "Peroxo group, Phenol, Sodium titanate, Titanium dioxide, Visible light",
author = "Tam{\'a}s Gyulav{\'a}ri and G{\'a}bor Ver{\'e}b and Zsolt Pap and A. Dombi and K. Hern{\'a}di",
year = "2018",
month = "1",
day = "1",
doi = "10.1016/j.cattod.2017.11.027",
language = "English",
journal = "Catalysis Today",
issn = "0920-5861",
publisher = "Elsevier",

}

TY - JOUR

T1 - Associating low crystallinity with peroxo groups for enhanced visible light active photocatalysts

AU - Gyulavári, Tamás

AU - Veréb, Gábor

AU - Pap, Zsolt

AU - Dombi, A.

AU - Hernádi, K.

PY - 2018/1/1

Y1 - 2018/1/1

N2 - In the present study hydrogen peroxide was applied during the synthesis of titanium dioxide (TiO2) photocatalysts to anchor peroxo groups onto the surface to enhance visible light excitability. The effect of changes in the pH value and crystallization temperature was investigated. As-prepared peroxo-titania were characterized by X-ray diffraction (XRD), diffuse reflectance spectroscopy (DRS), infrared spectroscopy (IR), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). The photocatalytic activity was investigated using phenol as model contaminant under visible light irradiation. IR and XPS measurements confirmed the presence of peroxo groups in the samples, moreover Raman and XPS measurements showed the formation of amorphous sodium titanate. Photocatalytic activity measurements pointed out, that most efficient as-prepared photocatalyst exceeded the photocatalytic performance of all reference materials. The cause of the enhanced photocatalytic activity was attributed to the enhanced visible light excitability and considerable amount of peroxo groups, which were not stable after the reusability experiments of the photocatalysts, suffering a redox reaction with the relatively high amount of Ti3+, resulting Ti4+ and surface OH groups. Therefore, the loss of peroxo groups and concomitantly photocatalytic activity was observed.

AB - In the present study hydrogen peroxide was applied during the synthesis of titanium dioxide (TiO2) photocatalysts to anchor peroxo groups onto the surface to enhance visible light excitability. The effect of changes in the pH value and crystallization temperature was investigated. As-prepared peroxo-titania were characterized by X-ray diffraction (XRD), diffuse reflectance spectroscopy (DRS), infrared spectroscopy (IR), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). The photocatalytic activity was investigated using phenol as model contaminant under visible light irradiation. IR and XPS measurements confirmed the presence of peroxo groups in the samples, moreover Raman and XPS measurements showed the formation of amorphous sodium titanate. Photocatalytic activity measurements pointed out, that most efficient as-prepared photocatalyst exceeded the photocatalytic performance of all reference materials. The cause of the enhanced photocatalytic activity was attributed to the enhanced visible light excitability and considerable amount of peroxo groups, which were not stable after the reusability experiments of the photocatalysts, suffering a redox reaction with the relatively high amount of Ti3+, resulting Ti4+ and surface OH groups. Therefore, the loss of peroxo groups and concomitantly photocatalytic activity was observed.

KW - Peroxo group

KW - Phenol

KW - Sodium titanate

KW - Titanium dioxide

KW - Visible light

UR - http://www.scopus.com/inward/record.url?scp=85044726260&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85044726260&partnerID=8YFLogxK

U2 - 10.1016/j.cattod.2017.11.027

DO - 10.1016/j.cattod.2017.11.027

M3 - Article

JO - Catalysis Today

JF - Catalysis Today

SN - 0920-5861

ER -