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: Spray Pyrolysis Technique (SPT) was used to deposit thin films (TFs) of cadmium stannate, doped with iron (Fe) for the first time. The precursor solutions that were used wereprepared at a concentration of 0.1M, doped with Feand then sprayed onto the pre-heated glass slides immediately at deposition temperatures of 350 ± 7°C, 400 ± 7°C and 450 ± 7°C. The optical properties of the deposited Fe-doped TFs were studied in the wavelength range of 300-1100nm. The X-Ray diffraction (XRD) studies showed that the TFs were orthorhombic with growth orientation along the (2 0 0) direction. Film thickness of 85 ± 10 nm was obtained. It was found out that anincrease in the deposition temperature increased transmittance and band gap, but decreased absorption coefficient, extinction coefficient and refractive index, which was attributed to the improvement in crystallinity of the deposited TFs. Doping reduced transmittance and band gap, but increased refractive index, absorption coefficient and extinction coefficient, which was attributed to the increase in free carriers. KEYWORDS:cadmium stannate, deposition temperature, iron-doped, optical properties of cadmium stannate
(Elsevier, 2020)
The elastic properties of the orthorhombic cadmium stannate (Cd2SnO4) were investigated using density functional theory, applying both energy-strain relationship (which is found in the literature) and stress-strain ...
Total electron content and scintillations over Maseno, Kenya, during high solar activity year
(Springer International Publishing, 2019)
Proper characterization of total electron content (TEC) and scintillation is very important to global positioning system (GPS) users in communication, navigation, ionospheric or atmospheric studies. Quiet time variation ...
Analysis of Loss Ratios Using a Mixed Linear Model
(University of Nairobi, 2008)
Loss ratios have been employed by a broad range of users for diverse purposes. Insurance companies, regulators, investors, rating agencies, investment analysts, lenders and others have used the loss ratio for their particular ...
An investigation of MHD Flows of Nanofluid over an oscillating surface with Joule Heating
(International Scientific Press, 2017)
The present study aims at investigating unsteady hydromagnetic flow of viscous
incompressible, conducting nanofluid over an infinite oscillating surface with
Joule heating. The governing equations involved are transformed ...
A numerical thermal growth model for prediction of microalgae production in photobioreactors
(AIP Publishing, 2016-03)
A thermal growth model for microalgae that are not heavier than water with the consideration of heat transfer and growth-temperature dependence in photobioreactor (PBR) is developed. The microalgae growth performance is ...
Microstructural and Elastic Properties of Stable Aluminium-rich TiAl and TiAl2 Formed Phase Intermetallics
(North-Holland, 2021)
We studied aluminium-rich Ti-Al (Ti32Al68 and Ti40Al60) binary alloys that were composed of TiAl and TiAl2 lamellar microstructures. The law of mixtures was employed in calculating the theoretical Young’s moduli. The lattice ...
Investigation of long acoustic waveguides for the very low frequency characterization of monolayer and stratified air-saturated poroelastic materials
(Elsevier, 2021)
When sound propagates in a porous medium, it is attenuated via several energy loss mechanisms which are switched on or off as the excitation frequency varies. The classical way of measuring acoustic energy loss in porous ...
Evaluating the effect of the substrate on the electrocatalytic performance of Cu2ZnSnS4 and Cu2ZnSnSe4 counter electrodes in dye-sensitized solar cells
(Elsevier, 2022)
The colloidal synthesis of Cu2ZnSnS4 (CZTS) and Cu2ZnSnSe4 (CZTSe) nanoparticles and their application as counter electrodes in dye-sensitized solar cells (DSSCs). In particular, the effect of three substrates namely; ...
Enhancing climate action at grassroots levels in least developed countries: unlocking bio-briquetting opportunities for communities in Wajir, Vihiga, Kitui, and Kajiado counties in Kenya
(Inderscience Publishers (IEL), 2021)
Grassroots communities are often the hardest hit by climate change. They also appreciably contribute to the problem through activities like deforestation, land use changes, and cooking with firewood. Bio-briquettes from ...
Ab initio study of elastic properties of orthorhombic cadmium stannate as a substrate for the manufacture of MEMS devices
(Science Direct, 2021)
The elastic properties of the orthorhombic cadmium stannate (Cd2SnO4) were investigated using density functional theory, applying both energy-strain relationship (which is found in the literature) and stress-strain ...