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Title: Electrosprayed heterojunction WO{sub 3}/BiVO{sub 4} films with nanotextured pillar structure for enhanced photoelectrochemical water splitting

Abstract

We demonstrate that the addition of a tungsten oxide (WO{sub 3}) layer beneath a bismuth vanadate (BiVO{sub 4}) photocatalyst layer with a nanotextured pillar morphology significantly increases the photocurrent density in photoelectrochemical water splitting. The WO{sub 3}-BiVO{sub 4} bilayer films produced a photocurrent of up to 3.3 mA/cm{sup 2} under illumination at 100 mW/cm{sup 2} (AM1.5 spectrum). The bilayer film was characterized by scanning electron microscopy, X-ray diffraction, and photoelectrochemical methods, which confirmed the superiority of the bilayer film in terms of its morphology and charge separation and transport ability. Both WO{sub 3} and BiVO{sub 4} were deposited by electrostatic spraying under open-air conditions, which resulted in nanotextured pillars of BiVO{sub 4} atop a smooth WO{sub 3} film. The optimal coating conditions are also reported.

Authors:
; ;  [1];  [1];  [2];  [3];  [4]
  1. School of Mechanical Engineering, Korea University, Seoul 136-713 (Korea, Republic of)
  2. (Korea, Republic of)
  3. Department of Chemistry and Biological Engineering, University at Buffalo (SUNY), Buffalo, New York 14260 (United States)
  4. Department of Chemistry, College of Science, King Saud University, Riyadh 11451 (Saudi Arabia)
Publication Date:
OSTI Identifier:
22398890
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 106; Journal Issue: 15; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; BISMUTH COMPOUNDS; ELECTROCHEMISTRY; FILMS; HETEROJUNCTIONS; ILLUMINANCE; LAYERS; MORPHOLOGY; PHOTOCURRENTS; SCANNING ELECTRON MICROSCOPY; TUNGSTEN OXIDES; WATER; X-RAY DIFFRACTION

Citation Formats

Mali, Mukund G., Yoon, Hyun, Yoon, Sam S., E-mail: skyoon@korea.ac.kr, Kim, Min-woo, Green School, Korea University, Seoul 136-713, Swihart, Mark T., and Al-Deyab, Salem S. Electrosprayed heterojunction WO{sub 3}/BiVO{sub 4} films with nanotextured pillar structure for enhanced photoelectrochemical water splitting. United States: N. p., 2015. Web. doi:10.1063/1.4918583.
Mali, Mukund G., Yoon, Hyun, Yoon, Sam S., E-mail: skyoon@korea.ac.kr, Kim, Min-woo, Green School, Korea University, Seoul 136-713, Swihart, Mark T., & Al-Deyab, Salem S. Electrosprayed heterojunction WO{sub 3}/BiVO{sub 4} films with nanotextured pillar structure for enhanced photoelectrochemical water splitting. United States. doi:10.1063/1.4918583.
Mali, Mukund G., Yoon, Hyun, Yoon, Sam S., E-mail: skyoon@korea.ac.kr, Kim, Min-woo, Green School, Korea University, Seoul 136-713, Swihart, Mark T., and Al-Deyab, Salem S. Mon . "Electrosprayed heterojunction WO{sub 3}/BiVO{sub 4} films with nanotextured pillar structure for enhanced photoelectrochemical water splitting". United States. doi:10.1063/1.4918583.
@article{osti_22398890,
title = {Electrosprayed heterojunction WO{sub 3}/BiVO{sub 4} films with nanotextured pillar structure for enhanced photoelectrochemical water splitting},
author = {Mali, Mukund G. and Yoon, Hyun and Yoon, Sam S., E-mail: skyoon@korea.ac.kr and Kim, Min-woo and Green School, Korea University, Seoul 136-713 and Swihart, Mark T. and Al-Deyab, Salem S.},
abstractNote = {We demonstrate that the addition of a tungsten oxide (WO{sub 3}) layer beneath a bismuth vanadate (BiVO{sub 4}) photocatalyst layer with a nanotextured pillar morphology significantly increases the photocurrent density in photoelectrochemical water splitting. The WO{sub 3}-BiVO{sub 4} bilayer films produced a photocurrent of up to 3.3 mA/cm{sup 2} under illumination at 100 mW/cm{sup 2} (AM1.5 spectrum). The bilayer film was characterized by scanning electron microscopy, X-ray diffraction, and photoelectrochemical methods, which confirmed the superiority of the bilayer film in terms of its morphology and charge separation and transport ability. Both WO{sub 3} and BiVO{sub 4} were deposited by electrostatic spraying under open-air conditions, which resulted in nanotextured pillars of BiVO{sub 4} atop a smooth WO{sub 3} film. The optimal coating conditions are also reported.},
doi = {10.1063/1.4918583},
journal = {Applied Physics Letters},
number = 15,
volume = 106,
place = {United States},
year = {Mon Apr 13 00:00:00 EDT 2015},
month = {Mon Apr 13 00:00:00 EDT 2015}
}
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