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Title: Enhanced photocatalytic activity of Ag microgrid connected TiO{sub 2} nanocrystalline films

Abstract

One reason for the high degree of photogenerated carrier recombination was found to be the charge accumulation caused by the uneven reaction area on the photocatalyst surface. The authors connected TiO{sub 2} nanoparticles with conducting Ag microgrid. Obvious photocatalytic activity improvement (81%) over the pure TiO{sub 2} was observed, which is attributed to the electron-hole pairs separation by the metal-semiconductor contact and the large specific area of metal grid, which increased the O{sub 2} absorption and transported the electrons to the sites needed for the deoxidize reactions. This structure lowers the electron accumulation on the particles and improves the utilization ratio of the photoexcited carriers.

Authors:
; ; ; ;  [1]
  1. Center of Materials Physics and Chemistry, Beihang University, Beijing 100083 (China)
Publication Date:
OSTI Identifier:
20960164
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 90; Journal Issue: 12; Other Information: DOI: 10.1063/1.2715477; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ABSORPTION; CRYSTALS; ELECTRIC CONTACTS; ELECTRONS; NANOSTRUCTURES; PARTICLES; PHOTOCATALYSIS; PHOTOCHEMISTRY; RECOMBINATION; SEMICONDUCTOR MATERIALS; SILVER; THIN FILMS; TITANIUM OXIDES

Citation Formats

Pan Feng, Zhang Junying, Zhang Weiwei, Wang Tianmin, and Cai Chao. Enhanced photocatalytic activity of Ag microgrid connected TiO{sub 2} nanocrystalline films. United States: N. p., 2007. Web. doi:10.1063/1.2715477.
Pan Feng, Zhang Junying, Zhang Weiwei, Wang Tianmin, & Cai Chao. Enhanced photocatalytic activity of Ag microgrid connected TiO{sub 2} nanocrystalline films. United States. doi:10.1063/1.2715477.
Pan Feng, Zhang Junying, Zhang Weiwei, Wang Tianmin, and Cai Chao. Mon . "Enhanced photocatalytic activity of Ag microgrid connected TiO{sub 2} nanocrystalline films". United States. doi:10.1063/1.2715477.
@article{osti_20960164,
title = {Enhanced photocatalytic activity of Ag microgrid connected TiO{sub 2} nanocrystalline films},
author = {Pan Feng and Zhang Junying and Zhang Weiwei and Wang Tianmin and Cai Chao},
abstractNote = {One reason for the high degree of photogenerated carrier recombination was found to be the charge accumulation caused by the uneven reaction area on the photocatalyst surface. The authors connected TiO{sub 2} nanoparticles with conducting Ag microgrid. Obvious photocatalytic activity improvement (81%) over the pure TiO{sub 2} was observed, which is attributed to the electron-hole pairs separation by the metal-semiconductor contact and the large specific area of metal grid, which increased the O{sub 2} absorption and transported the electrons to the sites needed for the deoxidize reactions. This structure lowers the electron accumulation on the particles and improves the utilization ratio of the photoexcited carriers.},
doi = {10.1063/1.2715477},
journal = {Applied Physics Letters},
number = 12,
volume = 90,
place = {United States},
year = {Mon Mar 19 00:00:00 EDT 2007},
month = {Mon Mar 19 00:00:00 EDT 2007}
}
  • In this work, a novel quaternary heterostructured Ag–Bi{sub 2}O{sub 2}CO{sub 3}/Bi{sub 3.64}Mo{sub 0.36}O{sub 6.55}/Bi{sub 2}MoO{sub 6} composite was fabricated through a low-temperature solution-phase route. The XRD, SEM, EDX and XPS results indicated the as-prepared sample is a four-phase composite of Bi{sub 2}O{sub 2}CO{sub 3}, Bi{sub 3.64}Mo{sub 0.36}O{sub 6.55}, Bi{sub 2}MoO{sub 6}, and Ag. The photocatalytic activities of the as-synthesized samples were evaluated towards the degradation of phenol red aqueous solution. The results showed that the as-synthesized Ag–Bi{sub 2}O{sub 2}CO{sub 3}/Bi{sub 3.64}Mo{sub 0.36}O{sub 6.55}/Bi{sub 2}MoO{sub 6} photocatalysts displayed much higher photocatalytic activities in comparison with pure Bi{sub 3.64}Mo{sub 0.36}O{sub 6.55}, puremore » Bi{sub 2}MoO{sub 6}, and Bi{sub 3.64}Mo{sub 0.36}O{sub 6.55}/Bi{sub 2}MoO{sub 6} composite. Among them, the 2.5% Ag–Bi{sub 2}O{sub 2}CO{sub 3}/Bi{sub 3.64}Mo{sub 0.36}O{sub 6.55}/Bi{sub 2}MoO{sub 6} sample performed the best. The enhanced photocatalytic activity of the composite photocatalyst was attributed predominantly to the efficient separation of photoinduced electrons and holes. In addition, Ag nanoparticles were photodeposited on the surface of the composite to increase visible-light absorption via the surface plasmon resonance, which is also beneficial to the enhancement of photocatalytic performance. The possible photocatalytic mechanism of the quaternary heterostructure was also discussed in detail. - Graphical abstract: Quaternary heterostructured Ag–Bi{sub 2}O{sub 2}CO{sub 3}/Bi{sub 3.64}Mo{sub 0.36}O{sub 6.55}/Bi{sub 2}MoO{sub 6} were fabricated. The as-synthesized Ag–Bi{sub 2}O{sub 2}CO{sub 3}/Bi{sub 3.64}Mo{sub 0.36}O{sub 6.55}/Bi{sub 2}MoO{sub 6} photocatalysts displayed much higher photocatalytic activities in comparison with pure Bi{sub 3.64}Mo{sub 0.36}O{sub 6.55}, pure Bi{sub 2}MoO{sub 6}, and Bi{sub 3.64}Mo{sub 0.36}O{sub 6.55}/Bi{sub 2}MoO{sub 6} composite. - Highlights: • Quaternary heterostructured Ag–Bi{sub 2}O{sub 2}CO{sub 3}/Bi{sub 3.64}Mo{sub 0.36}O{sub 6.55}/Bi{sub 2}MoO{sub 6} composites were fabricated. • Ag–Bi{sub 2}O{sub 2}CO{sub 3}/Bi{sub 3.64}Mo{sub 0.36}O{sub 6.55}/Bi{sub 2}MoO{sub 6} samples were characterized by various characterization technologies. • Ag–Bi{sub 2}O{sub 2}CO{sub 3}/Bi{sub 3.64}Mo{sub 0.36}O{sub 6.55}/Bi{sub 2}MoO{sub 6} composites presented excellent photocatalytic performances.« less
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