• F E Ghodsi

Articles written in Pramana – Journal of Physics

• Inﬂuence of drying conditions on the optical and structural properties of sol–gel-derived ZnO nanocrystalline ﬁlms

Zinc oxide nanothin ﬁlms were prepared on glass substrate by sol–gel dip-coating method using zinc acetate dihydrate, methanol, and monoethanolamine as precursor, solvent, and stabilizer, respectively. The relationship between drying conditions and the characteristics of ZnO nanocrystalline ﬁlms (𝑐-axis orientation, grain size, roughness and optical properties) was studied. The ﬁlms were dried in an oven at different temperatures and by IR radiation. Then, the ﬁlms were annealed at $500^{\circ}$C in a furnace. The chemical composition, transmission spectra, structure, and morphology of the samples were studied using infrared (IR) and UV–visible spectroscopy, X-ray diffraction (XRD), and atomic force microscopy (AFM), respectively. The XRD results show that the drying conditions affect the orientation of crystallization along the (0 0 2) plane. AFM images show that the thicknesses of the ﬁlms decrease from 128 to 93 nm by changing the drying conditions. The photoluminescence (PL) of ZnO nanothin ﬁlms shows the UV emission at near band edge and broad green radiation at about 465 nm wavelength.

• Preparation and investigation of optical, structural, and morphological properties of nanostructured ZnO:Mn thin films

Nanostructured ZnO:Mn thin films have been prepared by sol–gel dip coating method. The content of Mn in the sol was varied from 0 to 12 wt%. The effect of Mn concentration on the optical, structural, and morphological properties of ZnO thin films were studied by using Fourier transform infrared (FTIR), UV–visible and photoluminescence (PL) spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). XRD results showed that the films have hexagonal wurtzite structure at lower content of Mn. The diffraction peaks corresponding to ZnO disappeared and two diffraction peaks of MnO2 and Mn3O4 appeared at the highest value of doping concentration (viz., 12 wt$\%$). SEM results revealed that the surface smoothness of the films improved at higher content of Mn. The optical band gap of the films decreased from 3.89 to 3.15 eV when the Mn concentration increased from 0 to 12 wt$\%$. The PL spectra of the films showed the characteristic peaks linked to band-to-band, green and yellow emissions. Besides, the PL intensity of the samples decreased with increase in Mn concentration.

• # Pramana – Journal of Physics

Volume 96, 2022
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Continuous Article Publishing mode

• # Editorial Note on Continuous Article Publication

Posted on July 25, 2019