کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1458597 989580 2016 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Morphological, structural and ellipsometric investigations of Cr doped TiO2 thin films prepared by sol–gel and spin coating
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد سرامیک و کامپوزیت
پیش نمایش صفحه اول مقاله
Morphological, structural and ellipsometric investigations of Cr doped TiO2 thin films prepared by sol–gel and spin coating
چکیده انگلیسی

Pure and chromium doped titanium dioxide (TiO2) thin films at different atomic percentages (0.5%, 1.3% and 2.9%) have been elaborated on ITO/Glass substrates by sol–gel and spin–coating methods using titanium (IV) isopropoxide as a precursor. The surface morphology of films was investigated by scanning electron microscopy (SEM) and Atomic Force Microscopy (AFM), the structure was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and high resolution transmission microscopy (HRTEM). SEM and HRTEM show homogenous and polycrystalline films. XRD patterns indicate a phase transition from anatase to anatase-rutile leading to expand the absorption band of TiO2 molecules around 520 cm−1 in FTIR spectra. The optical constants such as the refractive index (n), the extinction coefficient (K) and the band gap (Eg) as well as the film thickness are determined using spectroscopic ellipsometry technique and Fourouhi–Blommer dispersion model. Results show three major changes; (i) the thickness of pure TiO2 layer is 54 nm, which linearly decreases when the layer is doped with chromium and reaches 33 nm for a doping concentration of 2.9%, (ii) the band gap energy (Eg) is also linearly reduced from 3.24 eV to 2.80 eV when the Cr-doping agent increases, and, (iii) a phase transition from anatase to anatase-rutile is observed causing an increase in values of n(λ) for wavelength greater than 350 nm.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Ceramics International - Volume 42, Issue 9, July 2016, Pages 10599–10607
نویسندگان
, , , ,