Çinko oksit nanotellerin çeşitli tuzlar ile sentezlenmesi üzerine parametrik çalışma


Tezin Türü: Yüksek Lisans

Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Mühendislik Fakültesi, Metalurji ve Malzeme Mühendisliği Bölümü, Türkiye

Tezin Onay Tarihi: 2012

Öğrenci: MEHMET CAN AKGÜN

Eş Danışman: RAŞİT TURAN, HÜSNÜ EMRAH ÜNALAN

Özet:

ZnO is a promising semiconducting material for manufacturing optoelectronic devices. Its most important properties are its wide and direct band gap and its high electron-hole binding energy. Synthesis of ZnO in bulk and thin film form has been investigated intensively over recent decades. Likewise, nanomaterials have been in the point of focus for their different properties compared to their bulk form. The vastly increased ratio of surface area to volume and change in electronic properties with great reduction in particle size enable improved performance in conventional applications where their bulk counterparts have been used for decades. As a result of this trend, research on synthesis of ZnO nanowires and their incorporation in prototype optoelectronic devices has been intensive in recent years. Therefore, synthesis of ZnO nanowires in a cost effective way and understanding the factors influencing the ZnO nanowire growth is essential for contribution to ongoing research. V In this thesis, hydrothermal synthesis of ZnO nanowires, which is a solution based method enabling vertically aligned ZnO nanowire array fabrication over large areas, is investigated. In the first part of this thesis, the effect of using various zinc salts as zinc sources on ZnO nanowires is investigated by monitoring pH, temperature and light transmittance of growth solutions. In the second part, a detailed parametric study on the use of zinc acetate dihydrate salt is provided with regard to the existence of its unique properties compared to other two zinc salts. The effect of growth time, temperature, ratio of concentration of precursor chemicals and precursor chemical concentrations is investigated. The results show that hydrothermal synthesis method could replace the conventional ZnO nanowire fabrication methods. It was shown that specific nanowire lengths for any application can be obtained simply by adjusting the parameters of hydrothermal growth system.