Dynamics of localized charges in dopamine-modified TiO and their effect on the formation of reactive oxygen species

Nada M. Dimitrijevic; Elena Rozhkova; Tijana Rajh

doi:10.1021/ja807654k

Dynamics of localized charges in dopamine-modified TiO and their effect on the formation of reactive oxygen species

Nada M. Dimitrijevic, Elena Rozhkova, Tijana Rajh

Research output: Contribution to journal › Article › peer-review

154 Scopus citations

Abstract

Modification of TiO ₂ nanoparticles with dopamine enables harvesting of visible light and promotes spatial separation of charges. The formation of reactive oxygen species (OH, ¹O ₂, O ₂ ^-, HO ₂, H ₂O ₂) upon illumination of TiO ₂/dopamine was studied using complementary spin-trap EPR and radical-induced fluorescence techniques. The localization of holes on dopamine suppresses oxidation of adsorbed water molecules at the surface of nanoparticles, and thus formation of OH radicals. At the same time, dopamine does not affect electronic properties of photogenerated electrons and their reaction with dissolved oxygen to produce superoxide anions. Superoxide anions are proposed to generate singlet oxygen through dismutation reaction, resulting in a low yield of ¹O ₂ detected.

Original language	English (US)
Pages (from-to)	2893-2899
Number of pages	7
Journal	Journal of the American Chemical Society
Volume	131
Issue number	8
DOIs	https://doi.org/10.1021/ja807654k
State	Published - Mar 4 2009
Externally published	Yes

ASJC Scopus subject areas

Catalysis
General Chemistry
Biochemistry
Colloid and Surface Chemistry

Access to Document

10.1021/ja807654k

Cite this

@article{3441c28ee55c4374992ef8e9c0d4a78a,

title = "Dynamics of localized charges in dopamine-modified TiO and their effect on the formation of reactive oxygen species",

abstract = "Modification of TiO 2 nanoparticles with dopamine enables harvesting of visible light and promotes spatial separation of charges. The formation of reactive oxygen species (OH, 1O 2, O 2 -, HO 2, H 2O 2) upon illumination of TiO 2/dopamine was studied using complementary spin-trap EPR and radical-induced fluorescence techniques. The localization of holes on dopamine suppresses oxidation of adsorbed water molecules at the surface of nanoparticles, and thus formation of OH radicals. At the same time, dopamine does not affect electronic properties of photogenerated electrons and their reaction with dissolved oxygen to produce superoxide anions. Superoxide anions are proposed to generate singlet oxygen through dismutation reaction, resulting in a low yield of 1O 2 detected.",

author = "Dimitrijevic, {Nada M.} and Elena Rozhkova and Tijana Rajh",

year = "2009",

month = mar,

day = "4",

doi = "10.1021/ja807654k",

language = "English (US)",

volume = "131",

pages = "2893--2899",

journal = "Journal of the American Chemical Society",

issn = "0002-7863",

publisher = "American Chemical Society",

number = "8",

}

TY - JOUR

T1 - Dynamics of localized charges in dopamine-modified TiO and their effect on the formation of reactive oxygen species

AU - Dimitrijevic, Nada M.

AU - Rozhkova, Elena

AU - Rajh, Tijana

PY - 2009/3/4

Y1 - 2009/3/4

N2 - Modification of TiO 2 nanoparticles with dopamine enables harvesting of visible light and promotes spatial separation of charges. The formation of reactive oxygen species (OH, 1O 2, O 2 -, HO 2, H 2O 2) upon illumination of TiO 2/dopamine was studied using complementary spin-trap EPR and radical-induced fluorescence techniques. The localization of holes on dopamine suppresses oxidation of adsorbed water molecules at the surface of nanoparticles, and thus formation of OH radicals. At the same time, dopamine does not affect electronic properties of photogenerated electrons and their reaction with dissolved oxygen to produce superoxide anions. Superoxide anions are proposed to generate singlet oxygen through dismutation reaction, resulting in a low yield of 1O 2 detected.

AB - Modification of TiO 2 nanoparticles with dopamine enables harvesting of visible light and promotes spatial separation of charges. The formation of reactive oxygen species (OH, 1O 2, O 2 -, HO 2, H 2O 2) upon illumination of TiO 2/dopamine was studied using complementary spin-trap EPR and radical-induced fluorescence techniques. The localization of holes on dopamine suppresses oxidation of adsorbed water molecules at the surface of nanoparticles, and thus formation of OH radicals. At the same time, dopamine does not affect electronic properties of photogenerated electrons and their reaction with dissolved oxygen to produce superoxide anions. Superoxide anions are proposed to generate singlet oxygen through dismutation reaction, resulting in a low yield of 1O 2 detected.

UR - http://www.scopus.com/inward/record.url?scp=68049109537&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=68049109537&partnerID=8YFLogxK

U2 - 10.1021/ja807654k

DO - 10.1021/ja807654k

M3 - Article

C2 - 19209860

AN - SCOPUS:68049109537

SN - 0002-7863

VL - 131

SP - 2893

EP - 2899

JO - Journal of the American Chemical Society

JF - Journal of the American Chemical Society

IS - 8

ER -

Dynamics of localized charges in dopamine-modified TiO and their effect on the formation of reactive oxygen species

Abstract

ASJC Scopus subject areas

Access to Document

Other files and links

Fingerprint

Cite this