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In present study, NiO:ZnO thin films in molar ratios of 1:0, 0:1, 3:1, 1:1 and 1:3 were formed on p-Si layers with Aluminium (Al) bottom contact. The dynamic sol-gel spin coating method was used as coating method. The Al top contacts were deposited on thin films and Al/NiO:ZnO/p-Si/Al photodiodes were fabricated. The structural and morphological properties of the photodiodes were determined by X-ray diffraction (XRD), emission scanning electron microscopy (FE-SEM), and energy dispersive X-ray spectroscopy (EDX). The photoresponse and electrical properties of the produced photodiodes were investigated by current-voltage (I-V) and capacitance-voltage (C-V) measurements. The Al/NiO:ZnO/p-Si/Al photodiodes were successfully fabricated. It was determined that the thin films were composed of nanostructures. All photodiodes are sensitive to light. It was seen that the photosensitivity of composite photodiodes was higher than the pure photodiodes and photosensitivity decreased as the ZnO ratio increased. It was determined that the most sensitive photodiode to light was the composite photodiode with a NiO:ZnO ratio of 3:1, and the highest photosensitivity was measured as 3.12 x 10 3 at 100 mW/cm 2 light intensity in this photodiode. In all photodiodes, the capacitance values decreased as the frequency increased. The results show that by changing the NiO:ZnO ratio, the photoresponse and electrical parameters of the photodiodes can be controlled and the produced photodiodes can be used as a photosensor in solar tracking systems and optoelectronic applications.

The purpose of this study is to determine the distribution and geochemical features of uranium mineralization in the Rağıllar region in the Manisa-Köprübaşı in western Turkey. Sixteen whole rock samples were collected from sites showing the highest levels of radioactivity (7600 cps) as measured by a gamma spectrometer in the dolomitic limestones. SEM-EDS (Scanning Electron Microscopy-Energy Dispersive Spectrometry), XRF (X-Ray Fluorescence), an ICP-OES (Inductively Coupled Plasma Optic Emission Spectrometer), and a Leco carbon-sulfur analyzer were used to determine the mineralogical and chemical characteristics of the whole rock samples. The mineralogical features showed that uranium mineralization is associated with fluorapatite-rich rocks formed within calcite matrix fractures; cracks systems; and limestone, claystone, marl and silicified breccia zones in the lacustrine sediments that are observed around the Kale crest dolomitic limestones in the Demirci basin. The geochemical data for these samples show a strong positive correlation between uranium and P2O5 concentrations. The geochemical data also indicate that uranium is deposited in the oxidation zone by dissolving the primary minerals (banded gneisses from the Menderes Massif, and dacitic and andesitic tuff) and moving the metal-rich hydrothermal fluids as phosphorus compounds, before passing through fractures, cracks, and permeable sandstone units, or along carbonate and clay layers.

Bu çalışmada, saf nikel oksit (NiO) ve Evropiyum (Eu) katkılı NiO nanoparçacıklar sol-jel yöntemi kullanılarak sentezlendi. Ni kaynağı olarak Nikel (II) asetat tetrahidrat ve Eu kaynağı olarak ise Evropiyum klorür kullanıldı. Sentezleme işlemi 80 ℃’ de 3 saat sürede gerçekleştirildi. Sentezlenen nanoparçacıklar 450 ℃’ de 1 saat süreyle tavlandı. Nanoparçacıkları oluşturan bileşikler X-ışını kırınımı (XRD) analiz edildi. Nanoparçacıkların morfolojileri alan emisyon taramalı elektron mikroskobu (FE-SEM) ile araştırıldı. Nanoparçacıkları oluşturan elementler ise enerji dağıtıcı X-ışını spektroskopisi (EDX) ile belirlendi. Sentezlenen parçacıkların nanoboyutta olduğu ve Eu katkısı ile morfolojilerin değiştiği görüldü. Eu katkısı arttıkça kafes parametreleri ve birim hücre hacimlerinin arttığı tespit edildi. Eu katkısı arttıkça kristalit boyutlarında azalma meydana gelmiştir. Yapısal ve morfolojik karakterizasyonlar neticesinde Eu katkısının başarıyla gerçekleştiği görüldü. Üretilen saf ve Eu katkılı NiO nanoparçacıkların yarıiletken endüstrisinde nanomalzeme olarak kullanım alanı bulabileceği sonucuna varıldı.