Physical and photocatalytic properties of sprayed Dy doped ZnO thin films under sunlight irradiation for degrading methylene blue

Dysprosium-doped zinc oxide (ZnO) thin films prepared through spray pyrolysis show outstanding photocatalytic activity for the degradation of methylene blue.

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Impact of Anionic Dopant Precursor on Nanostructured ZnO thin Films Surface Morphologies

Journal of the chemical society of pakistan ◽

10.52568/000683 ◽

2020 ◽

Vol 42 (5) ◽

pp. 713-713

Author(s):

Arshid Mahmood Ali Arshid Mahmood Ali ◽

Aishah Mahpudz Aishah Mahpudz ◽

Usman Saeed Usman Saeed ◽

Sami U Rather Sami U Rather ◽

Ayyaz M Nawaz Javaid A and Hui Zhang Ayyaz M Nawaz Javaid A and Hui Zhang

Keyword(s):

Thin Films ◽

Methylene Blue ◽

Photocatalytic Activity ◽

Hydrothermal Solution ◽

Ph Control ◽

Reaction Rate Constant ◽

Zno Thin Films ◽

Doped Zno ◽

Surface Morphologies ◽

The Impact

The aim of this study is to investigate the impact of an anionic precursor [N2 gas and triethyleneamine (TEA) as nitrogen dopant source] to prepare anionic doped ZnO thin films surface morphologies, via a novel route - hydrothermal solution deposition at low temperature. The effect of dopant concentration under both with and without pH control was studied. The less populated doped ZnO crystal nearly had the same band gap as compared to undoped ZnO thin films. The photocatalytic activity of selected doped ZnO thin films were studied for the degrdation of 10 mg L-1 Methylene Blue under UV irradiation of 254nm. Based on the 1st order reaction rate constant results the morphology N2:S2-MS has shown highest degradation followed by N:S1-MS. Overall, the photocatalytic activity order is N2:S2-MS andgt; N:S1-MS andgt; N:S2-CG andgt; N:S1-CG. In general, a significant variation in surface morphologies, crystal size and population, porosity and orientation were observed. This tailored-made variation enabled the doped ZnO thin films to successfully degrade the waste methylene blue effluents.

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Structural and Optical Characterization of Magnesium Doped Zinc Oxide Thin Films Deposited by Spray Pyrolysis

Dhaka University Journal of Science ◽

10.3329/dujs.v64i1.28516 ◽

2016 ◽

Vol 64 (1) ◽

pp. 1-6

Author(s):

Mitali Biswas ◽

Mehnaz Sharmin ◽

Chitra Das ◽

Jibon Poddar ◽

Shamima Choudhury

Keyword(s):

Thin Films ◽

Zinc Oxide ◽

Refractive Index ◽

Band Gap ◽

Spray Pyrolysis ◽

Zno Thin Films ◽

Zno Films ◽

Optical Parameters ◽

Doped Zno ◽

Mg Doped

Pure and magnesium (Mg) doped zinc oxide (ZnO) thin films were prepared onto clean glass substrate by spray pyrolysis (SP) technique at the substrate temperature of 300°C. Various optical parameters such as absorption co-efficient, band gap energy, refractive index, extinction coefficient of the thin films were studied using UV-VIS-NIR spectrophotometer in the photon wavelength range of 300-2500 nm. Optical band gap increased from 3.24 to 3.46 eV with the increase of Mg concentration from 0 to 40%. Transmittance and refractive index of the Mg doped ZnO thin films decreased due to the increase of Mg concentration. The EDX spectra confirmed the increase of Mg and consequent reduction in Zn content in the Mg doped ZnO thin films. Pure and Mg- doped ZnO films were annealed at 425°C for 1 hour. X-ray diffraction (XRD) study of the annealed films showed hexagonal type of polycry-stalline structure with the preferred orientation along (101) plane with some other peaks (100), (002), (102), (110), (103) and (112). From the XRD patterns it was found that grain size decreased from 63.45 to 36.56 nm, lattice constant _ and c remained almost constant with Mg doping concentration.Dhaka Univ. J. Sci. 64(1): 1-6, 2016 (January)

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