INFLUENCE OF PH ON THE STRUCTURAL AND MORPHOLOGICAL PROPERTIES OF ZnS THIN FILMS

Abstract

The ZnS thin films have been obtained from aqueous solution by means of cyclic voltammetry method. The electrochemical bath consisted of zinc sulphate, sodium thiosulfate and triethanolamine.

The effect of electrolyte pH on the properties of ZnS thin films was investigated within the range from 3 to 9. The cyclic voltammetry was used to analyse the electrochemical bath. The structural and morphological of thin films were investigated by X-ray diffraction and atomic force microscopy, respectively.

The thin films obtained have cubic structure and single phase as analysed by XRD. As the pH was reduced from 9 to 3, the intensities of the peaks corresponding to ZnS increased. AFM image shows the thin films prepared at pH 3 are homogeneous and well covered on the substrate. These thin films consist of small grains which lead to deposition of smoother films. However, as the pH increases up to 7, the number of grains decreases and larger grain size could be obtained. Therefore, the pH plays a major role in synthesis of ZnS thin film and the pH 3 is the best pH under current conditions.

Keywords

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Uygulamalı Bilimler ve Mühendislik

Abstract

ZnS ince filmler çevrimsel voltametri yöntemiyle sulu çözeltiden elde edilmiştir. Elektrokimyasal banyo çinko sülfat, sodyum tiosulfat ve triethnalomine içermiştir. ZnS yapısal özellikleri üzerine elktrolitin pH etkisi 3-9 aralıklar arasında incelenmiştir. Çevrimsel voltametri elektro-kimyasal banyoyu analiz etmek için kullanılmıştır. Atomik kuvvet mikroskopu ve X-ışınları (XRD) kırınımı analizleri ile ince filmler yapısal ve morfolojik olarak incelenmiştir. Zns yapılar kübik yapıda ve tek fazlı olduğu XRD sonuçlarından elde edilmiştir. pH değeri 9’dan 3’ e indirgendiğinde ZnS pik şiddetlerinin azaldığı gözlenmiştir. pH 3’de hazırlanan örneklerin kuvvet mikroskopu analizleri bu filmlerin alttaş ile uyumlu olarak büyüdüğü gösterilmiştir. Bu ince filmler bundan başka küçük tane büyüklüğüne sahip oldukları bu çalışmada gösterilmiştir. Diğer taraftan banyonun pH değeri 7’ye kadar arttırıldığına tane sayısı azalmış ve fakat tane büyüklüğü artmıştır. Böylece pH 3 değerindeki banyolamanın ince film hazırlamada önemli bir etkisi olduğu bu çalışma ile gösterilmiştir

Keywords

• Çevrimsel voltmetri, İnce film, Zinc sülfür, Metal kalgonide

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