A quantitative assessment of the competition between water and anion oxidation at WO 3 photoanodes in acidic aqueous electrolytes

Qixi Mi; Almagul Zhanaidarova; Bruce S. Brunschwig; Harry B. Gray; Nathan S. Lewis

doi:10.1039/c2ee02929d

A quantitative assessment of the competition between water and anion oxidation at WO ₃ photoanodes in acidic aqueous electrolytes

Qixi Mi, Almagul Zhanaidarova, Bruce S. Brunschwig, Harry B. Gray, Nathan S. Lewis

California Institute of Technology

Research output: Contribution to journal › Article

188 Citations (Scopus)

Abstract

The faradaic efficiency for O ₂(g) evolution at thin-film WO ₃ photoanodes has been evaluated in a series of acidic aqueous electrolytes. In 1.0 M H ₂SO ₄, persulfate was the predominant photoelectrochemical oxidation product, and no O ₂ was detected unless catalytic quantities of Ag ⁺(aq) were added to the electrolyte. In contact with 1.0 M HClO ₄, dissolved O ₂ was observed with nearly unity faradaic efficiency, but addition of a hole scavenger, 4-cyanopyridine N-oxide, completely suppressed O ₂ formation. In 1.0 M HCl, Cl ₂(g) was the primary oxidation product. These results indicate that at WO ₃ photoanodes, water oxidation is dominated by oxidation of the acid anions in 1.0 M HCl, H ₂SO ₄, and HClO ₄, respectively.

Original language	English
Pages (from-to)	5694-5700
Number of pages	7
Journal	Energy and Environmental Science
Volume	5
Issue number	2
DOIs	https://doi.org/10.1039/c2ee02929d
Publication status	Published - Feb 1 2012

Fingerprint

ASJC Scopus subject areas

Environmental Chemistry
Renewable Energy, Sustainability and the Environment
Nuclear Energy and Engineering
Pollution

Cite this

Mi, Q., Zhanaidarova, A., Brunschwig, B. S., Gray, H. B., & Lewis, N. S. (2012). A quantitative assessment of the competition between water and anion oxidation at WO ₃ photoanodes in acidic aqueous electrolytes. Energy and Environmental Science, 5(2), 5694-5700. https://doi.org/10.1039/c2ee02929d

@article{3a47dda864c1470ca70dfbc43ba0e857,

title = "A quantitative assessment of the competition between water and anion oxidation at WO 3 photoanodes in acidic aqueous electrolytes",

abstract = "The faradaic efficiency for O 2(g) evolution at thin-film WO 3 photoanodes has been evaluated in a series of acidic aqueous electrolytes. In 1.0 M H 2SO 4, persulfate was the predominant photoelectrochemical oxidation product, and no O 2 was detected unless catalytic quantities of Ag +(aq) were added to the electrolyte. In contact with 1.0 M HClO 4, dissolved O 2 was observed with nearly unity faradaic efficiency, but addition of a hole scavenger, 4-cyanopyridine N-oxide, completely suppressed O 2 formation. In 1.0 M HCl, Cl 2(g) was the primary oxidation product. These results indicate that at WO 3 photoanodes, water oxidation is dominated by oxidation of the acid anions in 1.0 M HCl, H 2SO 4, and HClO 4, respectively.",

author = "Qixi Mi and Almagul Zhanaidarova and Brunschwig, {Bruce S.} and Gray, {Harry B.} and Lewis, {Nathan S.}",

year = "2012",

month = feb

day = "1",

doi = "10.1039/c2ee02929d",

language = "English",

volume = "5",

pages = "5694--5700",

journal = "Energy and Environmental Science",

issn = "1754-5692",

publisher = "Royal Society of Chemistry",

number = "2",

}

TY - JOUR

T1 - A quantitative assessment of the competition between water and anion oxidation at WO 3 photoanodes in acidic aqueous electrolytes

AU - Mi, Qixi

AU - Zhanaidarova, Almagul

AU - Brunschwig, Bruce S.

AU - Gray, Harry B.

AU - Lewis, Nathan S.

PY - 2012/2/1

Y1 - 2012/2/1

N2 - The faradaic efficiency for O 2(g) evolution at thin-film WO 3 photoanodes has been evaluated in a series of acidic aqueous electrolytes. In 1.0 M H 2SO 4, persulfate was the predominant photoelectrochemical oxidation product, and no O 2 was detected unless catalytic quantities of Ag +(aq) were added to the electrolyte. In contact with 1.0 M HClO 4, dissolved O 2 was observed with nearly unity faradaic efficiency, but addition of a hole scavenger, 4-cyanopyridine N-oxide, completely suppressed O 2 formation. In 1.0 M HCl, Cl 2(g) was the primary oxidation product. These results indicate that at WO 3 photoanodes, water oxidation is dominated by oxidation of the acid anions in 1.0 M HCl, H 2SO 4, and HClO 4, respectively.

AB - The faradaic efficiency for O 2(g) evolution at thin-film WO 3 photoanodes has been evaluated in a series of acidic aqueous electrolytes. In 1.0 M H 2SO 4, persulfate was the predominant photoelectrochemical oxidation product, and no O 2 was detected unless catalytic quantities of Ag +(aq) were added to the electrolyte. In contact with 1.0 M HClO 4, dissolved O 2 was observed with nearly unity faradaic efficiency, but addition of a hole scavenger, 4-cyanopyridine N-oxide, completely suppressed O 2 formation. In 1.0 M HCl, Cl 2(g) was the primary oxidation product. These results indicate that at WO 3 photoanodes, water oxidation is dominated by oxidation of the acid anions in 1.0 M HCl, H 2SO 4, and HClO 4, respectively.

UR - http://www.scopus.com/inward/record.url?scp=84856754662&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84856754662&partnerID=8YFLogxK

U2 - 10.1039/c2ee02929d

DO - 10.1039/c2ee02929d

M3 - Article

AN - SCOPUS:84856754662

VL - 5

SP - 5694

EP - 5700

JO - Energy and Environmental Science

JF - Energy and Environmental Science

SN - 1754-5692

IS - 2

ER -

Access to Document

10.1039/c2ee02929d