Enhanced photocatalytic efficiency of NiS/TiO{sub 2} composite catalysts using sunset yellow, an azo dye under day light illumination

Journal Article · Thu Jan 15 00:00:00 EST 2015 · Materials Research Bulletin

DOI:https://doi.org/10.1016/J.MATERRESBULL.2014.09.095· OSTI ID:22420779

Rajamanickam, D.; Dhatshanamurthi, P.

Highlights: • NiS/TiO{sub 2} was successfully synthesized by sol–gel method. • This new method of preparation gives a homogeneous dispersion of NiS on TiO{sub 2}. • Degradation activity of NiS/TiO{sub 2} is found to be more efficient than other catalysts. • Addition of oxidants enhances the degradation efficiency significantly. • COD measurements reveal the complete mineralization of dye molecules. • The catalyst is found to be reusable. - Abstract: To improve the solar light induced photocatalytic application performances of TiO{sub 2}, in this study, the NiS modified TiO{sub 2} composite photocatalysts with various ratios of NiS to TiO{sub 2} were prepared by sol–gel method. The catalyst was characterized by X-ray diffraction (XRD), high resolution scanning electron microscope (HR-SEM), high resolution transmission electron microscope (HR-TEM), energy dispersive spectra (EDS), diffuse reflectance spectra (DRS), photoluminescence spectra (PL), X-ray photoelectron spectroscopy (XPS), and Brunauer–Emmett–Teller (B–E–T) surface area measurement methods. The photocatalytic activity of NiS/TiO{sub 2} was investigated for the degradation of sunset yellow (SY) in aqueous solution using solar light. The NiS/TiO{sub 2} is found to be more efficient than prepared TiO{sub 2} and TiO{sub 2}–P25 at pH 7 for the mineralization of SY. The effects of operational parameters such as the amount of photocatalyst, dye concentration and initial pH on photo mineralization of SY have been analyzed. The degradation was strongly enhanced in the presence of oxidants such as H{sub 3}K{sub 5}O{sub 18}S{sub 4} (Oxone), KIO{sub 4}, and KBrO{sub 3}. The mineralization of SY has been identified by COD measurements. The catalyst is found to be reusable.

• OSTI ID: 22420779
• Journal Information: Materials Research Bulletin, Vol. 61; Other Information: Copyright (c) 2014 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0025-5408
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
AQUEOUS SOLUTIONS
AZO DYES
BROMATES
COMPOSITE MATERIALS
MINERALIZATION
NICKEL SULFIDES
PHOTOCATALYSIS
PHOTOLUMINESCENCE
POTASSIUM COMPOUNDS
SCANNING ELECTRON MICROSCOPY
SEMICONDUCTOR MATERIALS
SOL-GEL PROCESS
SPECTRAL REFLECTANCE
TITANIUM OXIDES
TRANSMISSION ELECTRON MICROSCOPY
VISIBLE RADIATION
X-RAY DIFFRACTION
X-RAY PHOTOELECTRON SPECTROSCOPY
X-RAY SPECTROSCOPY