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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.


Related in: MedlinePlus

Schematic showing (A) the interfacial charge transfer between WO3and TiO2and (B) the direction of UV light.
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Fig6: Schematic showing (A) the interfacial charge transfer between WO3and TiO2and (B) the direction of UV light.

Mentions: In summary, a significant improvement in the aforementioned photoelectrochemical and photocatalytic processes of TiO2 was observed after surface modification with highly dispersed and very small size of WO3 nanoparticles. This effect could be attributed to the basic mechanism of photocatalysis. A significant amount of electrons and hole pairs could be generated upon illumination of catalyst’s surface with photons of appropriate energy. Unfortunately, most of the excited charge carriers (approximately 95%) go through the recombination process, in the absence of an effective electron transfer mechanism, which is a major energy-wasting process and overrides limitation of photocatalysts. When WO3 is effectively coupled with TiO2, the excited charge carriers undergo interfacial charge transfer phenomena and thus experience extended lifetime which in turn improved the photoelectrochemical and photocatalytic process. A plausible mechanism, based on the energy band diagram, showing the interfacial charge transfer between TiO2 and WO3 under UV light and applied anodic potential is presented in Figure 6A, together with schematic of WO3/TiO2/ITO layered structure (Figure 6B) [27].Figure 6


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)

Schematic showing (A) the interfacial charge transfer between WO3and TiO2and (B) the direction of UV light.
© Copyright Policy - open-access
Related In: Results  -  Collection

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

Fig6: Schematic showing (A) the interfacial charge transfer between WO3and TiO2and (B) the direction of UV light.
Mentions: In summary, a significant improvement in the aforementioned photoelectrochemical and photocatalytic processes of TiO2 was observed after surface modification with highly dispersed and very small size of WO3 nanoparticles. This effect could be attributed to the basic mechanism of photocatalysis. A significant amount of electrons and hole pairs could be generated upon illumination of catalyst’s surface with photons of appropriate energy. Unfortunately, most of the excited charge carriers (approximately 95%) go through the recombination process, in the absence of an effective electron transfer mechanism, which is a major energy-wasting process and overrides limitation of photocatalysts. When WO3 is effectively coupled with TiO2, the excited charge carriers undergo interfacial charge transfer phenomena and thus experience extended lifetime which in turn improved the photoelectrochemical and photocatalytic process. A plausible mechanism, based on the energy band diagram, showing the interfacial charge transfer between TiO2 and WO3 under UV light and applied anodic potential is presented in Figure 6A, together with schematic of WO3/TiO2/ITO layered structure (Figure 6B) [27].Figure 6

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.


Related in: MedlinePlus