Structural, Optical and Magnetic Properties of Nanocrystalline Cobalt Doped TiO₂ Prepared by Sol-Gel Route

Abstract:

Nanocrystalline Cobalt-doped TiO₂ was prepared by Sol-Gel technique, followed by freeze-drying treatment at-30°C temperature for 12hrs. The obtained Gel was thermally treated at 200,400,600, 800°C. 1%, 2% and 4% Cobalt doped TiO₂ nanopowder has been prepared X-ray Powder Diffraction (XRD), Scanning Electron microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDX), was used to study its structural properties. The XRD pattern shows the coexistence of anatase phase and rutile phase. Thermal gravimetric analysis shows Cobalt concentration affects thermal decomposition. UV-Vis Spectroscopy, Photo luminescence (PL), was used to study its Optical properties. Optical Bandgap were calculated with the incorporation of different concentration of cobalt. UV-Visible spectroscopy show variation in band gap for the sample treated at different temperature for same concentration. All Cobalt doped TiO₂ nanostructures shows an appearance of Red shift relative to the bulk TiO₂. The determination of magnetic properties was also carried out by Vibrating Sample Magnetometer.

• Periodical: Journal of Nano Research (Volume 24)
• Pages: 168-175
• DOI: https://doi.org/10.4028/www.scientific.net/JNanoR.24.168
• Online since: September 2013
• Authors: Kirit S. Siddhapara, D.V. Shah
• Keywords: Growth from Solution, Magnetic Material, Nanomaterial, Oxide, Sol-Gel Method, Titanium Compounds

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