Metal doped nanosized titania used for the photocatalytic degradation of rhodamine B dye under visible-light.

Metal doped nanosized titania used for the photocatalytic degradation of rhodamine B dye under visible-light.

Journal of nanoscience and nanotechnology (2013-08-02)

Mphilisi M Mahlambi, Ajay K Mishra, Shivani B Mishra, Rui W Krause, Bhekie B Mamba, Ashok M Raichur

ABSTRACT

Metal-doped anatase nanosized titania photocatalysts were successfully synthesized using a sol-gel process. Different amounts of the dopants (0.2, 0.4, 0.6, 0.8 and 1.0%) of the metals (Ag, Ni, Co and Pd) were utilized. The UV-Vis spectra (solid state diffuse reflectance spectra) of the doped nanoparticles exhibited a red shift in the absorption edge as a result of metal doping. The metal-doped nanoparticles were investigated for their photocatalytic activity under visible-light irradiation using Rhodamine B (Rh B) as a control pollutant. The results obtained indicate that the metal-doped titania had the highest activity at 0.4% metal loading. The kinetic models revealed that the photodegradation of Rh B followed a pseudo first order reaction. From ion chromatography (IC) analysis the degradation by-products Rhodamine B fragments were found to be acetate, chloride, nitrite, carbonate and nitrate ions.

MATERIALS

Product Number

Brand

Product Description

83689

Sigma-Aldrich

Rhodamine B, for fluorescence

79754

Supelco

Rhodamine B, analytical standard

R6626

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02558

Supelco

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204757

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224227

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635057

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204730

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700347

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637262

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634662

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248576

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677469

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637254

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232033

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348864

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