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Enhanced photoelectrochemical and photocatalytic activity of WO3-surface modified TiO2 thin film.

Qamar M, Drmosh Q, Ahmed MI, Qamaruddin M, Yamani ZH - Nanoscale Res Lett (2015)

Bottom Line: An enhancement in the photocurrent was observed when the TiO2 surface was modified WO3 nanoparticles.Photocatalytic activity of TiO2 and WO3-modified TiO2 for the decolorization of methyl orange was tested.Graphical abstractWO3-surface modified TiO2 film showing better photocatalytic and photoelectrocatalytic activity.

View Article: PubMed Central - PubMed

Affiliation: Center of Excellence in Nanotechnology (CENT), King Fahd University of Petroleum and Minerals (KFUPM), Box 498, Dhahran, 31261 Saudi Arabia.

ABSTRACT
Development of nanostructured photocatalysts for harnessing solar energy in energy-efficient and environmentally benign way remains an important area of research. Pure and WO3-surface modified thin films of TiO2 were prepared by magnetron sputtering on indium tin oxide glass, and photoelectrochemical and photocatalytic activities of these films were studied. TiO2 particles were <50 nm, while deposited WO3 particles were <20 nm in size. An enhancement in the photocurrent was observed when the TiO2 surface was modified WO3 nanoparticles. Effect of potential, WO3 amount, and radiations of different wavelengths on the photoelectrochemical activity of TiO2 electrodes was investigated. Photocatalytic activity of TiO2 and WO3-modified TiO2 for the decolorization of methyl orange was tested. Graphical abstractWO3-surface modified TiO2 film showing better photocatalytic and photoelectrocatalytic activity.

No MeSH data available.


Potentiodynamic behavior of TiO2with respect to the thickness of WO3layers.
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Fig2: Potentiodynamic behavior of TiO2with respect to the thickness of WO3layers.

Mentions: Coated side consisting of TiO2 or WO3/TiO2 of the electrodes was illuminated with UV light radiation, and obtained potentiodynamic behavior is shown in Figure 2. It is obvious from the figure that the photocurrent was increased with increasing the applied voltage. Figure 2 also demonstrates the effect of the thickness of WO3, which was deposited on TiO2 surface and controlled by deposition time, on the potentiodynamic response of electrodes. Using thickness monitoring, the thickness of TiO2 film was calculated to approximately 170 nm, whereas the thickness of deposited WO3 layers was calculated to be about 10, 20, 45, and 90 nm for 1, 2.5, 5.0, and 10 min, respectively. It is interesting to note that the photocurrent density was found to increase with the increase in WO3 amount up to a critical amount, and a further increase failed to contribute positively on the overall photocurrent efficiency of the electrode. The overall effect of WO3 amounts on TiO2 surface was more significant at or higher than 0.6 V. This behavior may be explained in terms of interfacial electron transfer between WO3 and TiO2 as well as the extent of TiO2 surface coverage by WO3. In case of partial or optimum coverage of the TiO2 surface by WO3 particles, both oxide surfaces may absorb incident photons and generate charge carriers, which may undergo an interfacial charge transfer process thereby enhancing the overall flow of current. On the other hand, when the coverage of TiO2 surface by WO3 exceeds the critical limit or TiO2 surface is mostly covered by WO3, photons will largely be absorbed by WO3 ensuing lesser generation of electrons or photocurrents, noting the fact that WO3 is an intrinsically less active photocatalyst than TiO2.Figure 2


Enhanced photoelectrochemical and photocatalytic activity of WO3-surface modified TiO2 thin film.

Qamar M, Drmosh Q, Ahmed MI, Qamaruddin M, Yamani ZH - Nanoscale Res Lett (2015)

Potentiodynamic behavior of TiO2with respect to the thickness of WO3layers.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4385024&req=5

Fig2: Potentiodynamic behavior of TiO2with respect to the thickness of WO3layers.
Mentions: Coated side consisting of TiO2 or WO3/TiO2 of the electrodes was illuminated with UV light radiation, and obtained potentiodynamic behavior is shown in Figure 2. It is obvious from the figure that the photocurrent was increased with increasing the applied voltage. Figure 2 also demonstrates the effect of the thickness of WO3, which was deposited on TiO2 surface and controlled by deposition time, on the potentiodynamic response of electrodes. Using thickness monitoring, the thickness of TiO2 film was calculated to approximately 170 nm, whereas the thickness of deposited WO3 layers was calculated to be about 10, 20, 45, and 90 nm for 1, 2.5, 5.0, and 10 min, respectively. It is interesting to note that the photocurrent density was found to increase with the increase in WO3 amount up to a critical amount, and a further increase failed to contribute positively on the overall photocurrent efficiency of the electrode. The overall effect of WO3 amounts on TiO2 surface was more significant at or higher than 0.6 V. This behavior may be explained in terms of interfacial electron transfer between WO3 and TiO2 as well as the extent of TiO2 surface coverage by WO3. In case of partial or optimum coverage of the TiO2 surface by WO3 particles, both oxide surfaces may absorb incident photons and generate charge carriers, which may undergo an interfacial charge transfer process thereby enhancing the overall flow of current. On the other hand, when the coverage of TiO2 surface by WO3 exceeds the critical limit or TiO2 surface is mostly covered by WO3, photons will largely be absorbed by WO3 ensuing lesser generation of electrons or photocurrents, noting the fact that WO3 is an intrinsically less active photocatalyst than TiO2.Figure 2

Bottom Line: An enhancement in the photocurrent was observed when the TiO2 surface was modified WO3 nanoparticles.Photocatalytic activity of TiO2 and WO3-modified TiO2 for the decolorization of methyl orange was tested.Graphical abstractWO3-surface modified TiO2 film showing better photocatalytic and photoelectrocatalytic activity.

View Article: PubMed Central - PubMed

Affiliation: Center of Excellence in Nanotechnology (CENT), King Fahd University of Petroleum and Minerals (KFUPM), Box 498, Dhahran, 31261 Saudi Arabia.

ABSTRACT
Development of nanostructured photocatalysts for harnessing solar energy in energy-efficient and environmentally benign way remains an important area of research. Pure and WO3-surface modified thin films of TiO2 were prepared by magnetron sputtering on indium tin oxide glass, and photoelectrochemical and photocatalytic activities of these films were studied. TiO2 particles were <50 nm, while deposited WO3 particles were <20 nm in size. An enhancement in the photocurrent was observed when the TiO2 surface was modified WO3 nanoparticles. Effect of potential, WO3 amount, and radiations of different wavelengths on the photoelectrochemical activity of TiO2 electrodes was investigated. Photocatalytic activity of TiO2 and WO3-modified TiO2 for the decolorization of methyl orange was tested. Graphical abstractWO3-surface modified TiO2 film showing better photocatalytic and photoelectrocatalytic activity.

No MeSH data available.