Bicarbonate-enhanced generation of hydroxyl radical by visible light-induced photocatalysis of H2O2 over WO3: Alteration of electron transfer mechanism

Jaemin Choi; Hak–Hyeon –H Kim; Ki–Myeong –M Lee; Na Chen; Min Sik Kim; Jiwon Seo; Donghyun Lee; Haein Cho; Hyoung il Kim; Jaesang Lee; Hongshin Lee; Changha Lee

doi:10.1016/j.cej.2021.134401

Bicarbonate-enhanced generation of hydroxyl radical by visible light-induced photocatalysis of H₂O₂ over WO₃: Alteration of electron transfer mechanism

Jaemin Choi
, Hak–Hyeon –H Kim
, Ki–Myeong –M Lee
, Na Chen
, Min Sik Kim
, Jiwon Seo
, Donghyun Lee
, Haein Cho
, Hyoung il Kim
, Jaesang Lee
, Hongshin Lee^*
, Changha Lee

^*Corresponding author for this work

Environmental Engineering

Korea University
University of Waterloo
Seoul National University
National Institute of Environmental Research
Yonsei University

Research output: Contribution to journal › Journal article › peer-review

49 Scopus citations

Abstract

The generation of hydroxyl radical (^•OH) by visible light-illuminated tungsten oxide (WO₃) was found to be significantly improved in the presence of hydrogen peroxide (H₂O₂) and bicarbonate ion (HCO₃⁻). A ternary system of hν/WO₃/H₂O₂/HCO₃⁻ showed synergistic enhancement in oxidation of benzoic acid (BA, a ^•OH probe compound) into hydroxybenzoic acids (HBAs), exhibiting even less consumption of H₂O₂ than hν/WO₃/H₂O₂. Analyses of HBAs from BA oxidation (three HBA isomers and ¹⁸O-labelled HBA from H₂¹⁸O₂) suggested that hν/WO₃/H₂O₂/HCO₃⁻, contrary to hν/WO₃/H₂O₂, generated ^•OH mainly via one-electron transfer from the conduction band of WO₃ to H₂O₂. The dominant one-electron reduction of H₂O₂ over HCO₃⁻-treated WO₃ was further evidenced by Koutecký–Levich plots obtained with a rotating disk electrode setup. Based on different experiments using electron paramagnetic resonance spectroscopy, radical scavengers and probes, (photo-)electrochemical measurements, and density functional theory calculations, the mechanisms underlying the enhanced generation of ^•OH by hν/WO₃/H₂O₂/HCO₃⁻ were discussed.

Original language	English
Article number	134401
Journal	Chemical Engineering Journal
Volume	432
DOIs	https://doi.org/10.1016/j.cej.2021.134401
State	Published - 2022.03.15

Keywords

Bicarbonate
Hydrogen peroxide
Hydroxyl radical
Photocatalysis
Tungsten oxide

Quacquarelli Symonds(QS) Subject Topics

Environmental Sciences
Engineering - Mechanical
Engineering - Petroleum
Engineering - Chemical
Chemistry

Access to Document

10.1016/j.cej.2021.134401

Cite this

Choi, J., Kim, HH. H., Lee, KM. M., Chen, N., Kim, M. S., Seo, J., Lee, D., Cho, H., Kim, H. I., Lee, J., Lee, H., & Lee, C. (2022). Bicarbonate-enhanced generation of hydroxyl radical by visible light-induced photocatalysis of H₂O₂ over WO₃: Alteration of electron transfer mechanism. Chemical Engineering Journal, 432, Article 134401. https://doi.org/10.1016/j.cej.2021.134401

@article{e78a51d1c0a847c89dfa4de79973ede0,

title = "Bicarbonate-enhanced generation of hydroxyl radical by visible light-induced photocatalysis of H2O2 over WO3: Alteration of electron transfer mechanism",

abstract = "The generation of hydroxyl radical (•OH) by visible light-illuminated tungsten oxide (WO3) was found to be significantly improved in the presence of hydrogen peroxide (H2O2) and bicarbonate ion (HCO3−). A ternary system of hν/WO3/H2O2/HCO3− showed synergistic enhancement in oxidation of benzoic acid (BA, a •OH probe compound) into hydroxybenzoic acids (HBAs), exhibiting even less consumption of H2O2 than hν/WO3/H2O2. Analyses of HBAs from BA oxidation (three HBA isomers and 18O-labelled HBA from H218O2) suggested that hν/WO3/H2O2/HCO3−, contrary to hν/WO3/H2O2, generated •OH mainly via one-electron transfer from the conduction band of WO3 to H2O2. The dominant one-electron reduction of H2O2 over HCO3−-treated WO3 was further evidenced by Kouteck{\'y}{\textendash}Levich plots obtained with a rotating disk electrode setup. Based on different experiments using electron paramagnetic resonance spectroscopy, radical scavengers and probes, (photo-)electrochemical measurements, and density functional theory calculations, the mechanisms underlying the enhanced generation of •OH by hν/WO3/H2O2/HCO3− were discussed.",

keywords = "Bicarbonate, Hydrogen peroxide, Hydroxyl radical, Photocatalysis, Tungsten oxide",

author = "Jaemin Choi and Kim, \{Hak{\textendash}Hyeon {\textendash}H\} and Lee, \{Ki{\textendash}Myeong {\textendash}M\} and Na Chen and Kim, \{Min Sik\} and Jiwon Seo and Donghyun Lee and Haein Cho and Kim, \{Hyoung il\} and Jaesang Lee and Hongshin Lee and Changha Lee",

note = "Publisher Copyright: {\textcopyright} 2021 Elsevier B.V.",

year = "2022",

month = mar,

day = "15",

doi = "10.1016/j.cej.2021.134401",

language = "English",

volume = "432",

journal = "Chemical Engineering Journal",

issn = "1385-8947",

}

TY - JOUR

T1 - Bicarbonate-enhanced generation of hydroxyl radical by visible light-induced photocatalysis of H2O2 over WO3

T2 - Alteration of electron transfer mechanism

AU - Choi, Jaemin

AU - Kim, Hak–Hyeon –H

AU - Lee, Ki–Myeong –M

AU - Chen, Na

AU - Kim, Min Sik

AU - Seo, Jiwon

AU - Lee, Donghyun

AU - Cho, Haein

AU - Kim, Hyoung il

AU - Lee, Jaesang

AU - Lee, Hongshin

AU - Lee, Changha

PY - 2022/3/15

Y1 - 2022/3/15

N2 - The generation of hydroxyl radical (•OH) by visible light-illuminated tungsten oxide (WO3) was found to be significantly improved in the presence of hydrogen peroxide (H2O2) and bicarbonate ion (HCO3−). A ternary system of hν/WO3/H2O2/HCO3− showed synergistic enhancement in oxidation of benzoic acid (BA, a •OH probe compound) into hydroxybenzoic acids (HBAs), exhibiting even less consumption of H2O2 than hν/WO3/H2O2. Analyses of HBAs from BA oxidation (three HBA isomers and 18O-labelled HBA from H218O2) suggested that hν/WO3/H2O2/HCO3−, contrary to hν/WO3/H2O2, generated •OH mainly via one-electron transfer from the conduction band of WO3 to H2O2. The dominant one-electron reduction of H2O2 over HCO3−-treated WO3 was further evidenced by Koutecký–Levich plots obtained with a rotating disk electrode setup. Based on different experiments using electron paramagnetic resonance spectroscopy, radical scavengers and probes, (photo-)electrochemical measurements, and density functional theory calculations, the mechanisms underlying the enhanced generation of •OH by hν/WO3/H2O2/HCO3− were discussed.

AB - The generation of hydroxyl radical (•OH) by visible light-illuminated tungsten oxide (WO3) was found to be significantly improved in the presence of hydrogen peroxide (H2O2) and bicarbonate ion (HCO3−). A ternary system of hν/WO3/H2O2/HCO3− showed synergistic enhancement in oxidation of benzoic acid (BA, a •OH probe compound) into hydroxybenzoic acids (HBAs), exhibiting even less consumption of H2O2 than hν/WO3/H2O2. Analyses of HBAs from BA oxidation (three HBA isomers and 18O-labelled HBA from H218O2) suggested that hν/WO3/H2O2/HCO3−, contrary to hν/WO3/H2O2, generated •OH mainly via one-electron transfer from the conduction band of WO3 to H2O2. The dominant one-electron reduction of H2O2 over HCO3−-treated WO3 was further evidenced by Koutecký–Levich plots obtained with a rotating disk electrode setup. Based on different experiments using electron paramagnetic resonance spectroscopy, radical scavengers and probes, (photo-)electrochemical measurements, and density functional theory calculations, the mechanisms underlying the enhanced generation of •OH by hν/WO3/H2O2/HCO3− were discussed.

KW - Bicarbonate

KW - Hydrogen peroxide

KW - Hydroxyl radical

KW - Photocatalysis

KW - Tungsten oxide

UR - https://www.scopus.com/pages/publications/85123267399

U2 - 10.1016/j.cej.2021.134401

DO - 10.1016/j.cej.2021.134401

M3 - Journal article

AN - SCOPUS:85123267399

SN - 1385-8947

VL - 432

JO - Chemical Engineering Journal

JF - Chemical Engineering Journal

M1 - 134401

ER -