Browsing by Keywords "XRD"

Analysis of the mosaic defects in graded and non graded InxGa1‐xN solar cell structures

Kars Durukan, İ.; Öztürk, M. K.; Özçelik, S.; Özbay, Ekmel (Süleyman Demirel Üniversitesi, 2017)

In this study, graded (A) InxGa1‐xN (10.5 ≤ x ≤ 18.4) and non graded (B) InxGa1‐xN (13.6 ≤ x ≤ 24.9) samples are grown on c‐oriented sapphire substrate using the Metal Organic Chemical Vapour Deposition (MOCVD) technique. ...

Analyzing the AlGaN/AlN/GaN heterostructures for HEMT applications

K. Durukan, İ.; Akpınar, Ö.; Avar, C.; Gultekin, A.; Öztürk, M. K.; Özçelik, S.; Özbay, Ekmel (American Scientific Publishers, 2018-03)

In the present work, we have reported two high-electron-mobility transistor structures (HEMTs) with different thick AlN buffer deposited on sapphire substrates by metal-organic chemical vapor deposition (MOCVD). AlN buffer ...

Carbon supported nano-sized Pt-Pd and Pt-Co electrocatalysts for proton exchange membrane fuel cells

Kadirgan, F.; Kannan, A. M.; Atilan, T.; Beyhan, S.; Ozenler, S. S.; Süzer, Şefik; Yörür, A. (2009)

Nano-sized Pt-Pd/C and Pt-Co/C electrocatalysts have been synthesized and characterized by an alcohol-reduction process using ethylene glycol as the solvent and Vulcan XC-72R as the supporting material. While the Pt-Pd/C ...

Ceria promoted NOx storage and reduction materials

Say, Zafer (Bilkent University, 2011)

In the current work, the effect of CeO2 promotion on the NOx storage materials and NOx storage-reduction (NSR) catalysts is studied. Synthesized materials were prepared using different baria and ceria loadings in order ...

Collagen-chitosan scaffold modified with Au and Ag nanoparticles: synthesis and structure

Rubina, M. S.; Kamitov, E. E.; Zubavichus, Y. V.; Peters, G. S.; Naumkin, A. V.; Süzer, Şefik; Vasil'kov, A. Y. (Elsevier B.V., 2016)

Nowadays, the dermal biomimetic scaffolds are widely used in regenerative medicine. Collagen-chitosan scaffold one of these materials possesses antibacterial activity, good compatibility with living tissues and has been ...

Examination of the temperature related structural defects of InGaN/GaN solar cells

Durukan, İ. K.; Bayal, Ö.; Kurtuluş, G.; Baş, Y.; Gültekin, A.; Öztürk, M. K.; Çörekçi, S.; Tamer, M.; Özçelik, S.; Özbay, Ekmel (Academic Press, 2015)

In this study the effects of the annealing temperature on the InGaN/GaN solar cells with different In-contents grown on sapphire substrate by the Metal Organic Chemical Vapor Deposition (MOCVD) are analyzed by High Resolution ...

Fe promoted NOx storage materials: structural properties and NOx uptake

Kayhan, E.; Andonova, S. M.; Şentürk, G. S.; Chusuei, C. C.; Ozensoy, E. (American Chemical Society, 2010)

Fe promoted NOx storage materials were synthesized in the form of FeOx/BaO/Al2O3 ternary oxides with varying BaO (8 and 20 wt %) and Fe (5 and 10 wt %) contents. Synthesized NOx storage materials were investigated via TEM, ...

Fine-tuning the dispersion and the mobility of BaO domains on NO x storage materials via TiO2 anchoring sites

Andonova, S. M.; Şentürk, G. S.; Ozensoy, E. (American Chemical Society, 2010)

In an attempt to control the surface dispersion and the mobility of BaO domains on NOx storage materials, TiO2/TiOx anchoring sites were introduced on/inside the conventional γ-Al 2O3 support matrix. BaO/TiO2/Al 2O3 ternary ...

Gold catalysts supported on ceria doped by rare earth metals for water gas shift reaction: influence of the preparation method

Andreeva, D.; Ivanov, I.; Ilieva, L.; Abrashev, M. V.; Zanella, R.; Sobczak, J. W.; Lisowski, W.; Kantcheva, M.; Avdeev, G.; Petrov, K. (2009)

Gold catalysts based on ceria, doped by various RE metals (La, Sm, Gd, Yb, Y) were studied. The influence of the preparation methods on structure, properties and catalytic activity in the WGS reaction was investigated. The ...

InGaN/GaN LED yapıların mozaik yapı analizi

Durukan, İ. K.; Öztürk, M. K.; Özçelik, S.; Özbay, Ekmel (Osman Sağdıç, 2018)

Bu çalışmada, MOCVD yöntemi ile üretilen InGaN/GaN ışık yayan diyot (LED) yapılarının mozaik yapıları analiz edildi. Safir alttaş üzerine biriktirilen, farklı In kompozisyonuna sahip InGaN/GaN bariyer tabakasının mozaik ...

Investigation of the crystallinity and orientation of polypropylene with respect to temperature changes using FT-IR, WRD, and Raman techniques

Türkçü, Harun Nezih (Bilkent University, 2004)

Having good mechanical and barrier properties, polypropylene films are widely used in food-packing industry. The relation of crystallinity and orientation of polypropylene with these properties are well known. Temperature ...