مديحه أحمد أبو الفضل عوض

مدرس - مدرس

كلية العلوم

العنوان: شارع 63 متفرع من شارع جمال عبد الناصر( العشرين) -مدينة ناصر


2018 | الكلمات المفتاحية multilayers, Resistivity, Optical ,
Optical and electrical performance of transparent conductive TiO2/ Cu/TiO2 multilayers prepared by magnetron sputtering
TiO2/Cu/TiO2 (TCT) multilayers were deposited by dc pulsed magnetron sputtering on glass substrates for the possible use as transparent conducting oxide (TCO). The thicknesses of copper ( Cud) interlayers were 0, 8, 10, 12, 13 and 15 nm. The changes in structural, optical and electrical properties of the TCT multilayers have been investigated as a function of Cud. XRD examination ... إقراء المزيد

2018 | الكلمات المفتاحية thermal oxidation, nanoparticles, Optical ,
The disclosed transformation of pre-sputtered Ti films into nanoparticles via controlled thermal oxidation
Nanoparticles of TiO2 were successfully prepared from pre-sputtered Ti films using the controlled thermal oxidation. The effect of oxidation temperature on structural, morphological and optical properties in addition to photocatalysis activity of the sputtered films was tested and explained. Analysis of XRD and EDAX elucidated the enhancement in crystallization and oxygen content with the increase of oxidation temperature. SEM depicted ... إقراء المزيد

2017 | الكلمات المفتاحية Copper oxides Thermal treatmen,
Copper oxide nanocrystallites fabricated by thermal oxidation of pre-sputtered copper films at different temperatures and under oxygen and argon flows
Copper oxide nanocrystallites were synthesized from Cu thin films via controlled thermal treatment under O2 and Ar flows. The nanocrystallites were synthesized at 350, 400 and 500 ◦C. XRD revealed that substoichiometric copper oxides such as Cu4O3 and Cu64O were emerged with Cu and CuO for samples treated at 350 ◦C and 450 ◦C, respectively, whereas single monoclinic CuO was ... إقراء المزيد

2016 | الكلمات المفتاحية hydrotherma, electrical, optic,
Optical and electrical properties of hydrothermally prepared CdTe nanowires
The hydrothermal process was used to synthesize CdTe nanowires (NWs). Various analytical techniques were used to characterize the obtained NWs. The wire diameters were in the range 35–60 nm, and the lengths were [5 lm. The CdTe NWs had zinc-blende crystal structure. The NWs had high uniformity and high yield. FTIR analysis revealed the presence of the characteristic vibrational spectra ... إقراء المزيد

2015 | الكلمات المفتاحية photocatalysis, XRD, SEM,
One step syntheses of S incorporated ZnO nanowires for photocatalysis applications
S incorporated ZnO nanowires (NWs) were prepared by vapor transport method using ZnS bulk precursor. Effects of S incorporation on the structural, morphological, optical as well as photocatalysis performance of ZnO NWs were studied. EDAX analysis revealed existence of S with low ratio. A deformation of the hexagonal nanowires was observed inasmuch to the S existence. X-ray diffraction analysis asserted ... إقراء المزيد

2015 | الكلمات المفتاحية ZnO NWs; Vapor transport; grow,
The Effect of Temperature and Oxygen Flow Rate on the Morphology of ZnO Nanostructures
Three different morphologies of ZnO nanostructures were prepared by vapor transport on Au coated silicon substrates. Randomly oriented nanowires (NWs) mixed with few nanoflakes were obtained at furnace temperature of 750 °C and oxygen flow rate of 20 sccm. While thicker, longer and denser NWs were obtained at furnace temperature of 900 °C with the same oxygen flow rate of ... إقراء المزيد

2015 | الكلمات المفتاحية Electricalconductivity;C.Optic,
Tuning themorphologyofZnOnanostructurebyindoping and theassociatedvariationinelectricalandopticalproperties
In thiswork,Zn100xInx (x¼0, 1,2.5,5and7.5at%)compoundshavebeeninitiallyalloyedbymeltingmethodandusedasprecursorsto prepare differentnanostructuresofindium(In)dopedZnOusingchemicalvapordeposition(CVD).TheeffectofIncontentonthestructural, morphological, opticalaswellaselectricalpropertieshasbeenstudied.XRDandRamanexaminationsdemonstratethesubstitutionofZnþ2 ions by Inþ3 ions atlowerindiumconcentrations,whileIn2O3 appears asseparatephaseathigherInratios.Thenanowirestransformtonanoflakes then nanoflowers astheInconcentrationincreases.Withregardtotheopticalproperties,thetransparencyincreaseswithincreasingInand decreases thereafter.TheopticalbandgapvaluesincreasewithIncontentreachingitsmaximumvalue(3.28eV)forthesampleof x¼5 at%.The refractive index,extinctioncoefficient andUrbachtailarealsoaffectedbyIndoping.Theelectricalconductivityenhancesatlowerdopinglevel due toformationofthermallyactivateddonorlevels,despitethis,thephaseseparationandphononscatteringarefactorsresponsiblefor conductivity decreaseathigherIncontent. إقراء المزيد

2014 | الكلمات المفتاحية ZnO NWs  Vapor transport  An,
Synthesis and thermal stability of ZnO nanowires
ZnO nanowires (NWs) were synthesized on Au-coated Si (100) substrates by vapor transport method. The effect of high temperature annealing on the structural and chemical composition as well as thermal stability was studied. The as-prepared ZnO NWs was nearly stoichiometric and identified as hexagonal ZnO phase. After annealing at 1,473 K, the atomic ratio of O/Zn, the intensity of the ... إقراء المزيد

2008 | الكلمات المفتاحية X-ray diffraction – 73.61.-r E,
Optical and electrical properties of Sn-Sb-Se chalcogenide thin films
The optical and electrical properties of the as-prepared and annealed SnxSb20Se80−x (where x = 8, 10, 12, 13.5, 15, 16.5 and 18 at.%) thin films were studied. X-ray diffraction showed that all the as-prepared Sn-Sb-Se films were amorphous. Annealing the films at 473 K or above crystallized the films and the degree of crystallinity depended on the Sn content. The ... إقراء المزيد

2007 | الكلمات المفتاحية chalcogenide materials,
Structural and kinetic evaluation of Sn–Sb–Se alloys
Abstract SnxSb20Se80-x chalcogenide alloys (with x = 8, 10, 12, 13.5, 15, 16.5 and 18 at.%) were prepared by the melt quenching technique. The average coordination number and the overall mean bonding energy were calculated. The x-ray diffraction studies revealed that the alloys with x = 8 and 10 at.% were amorphous and the alloy with x = 12 at.% ... إقراء المزيد