X-Ray Analysis of Cadmium Oxide Nanostructured Films Synthesized with Different Precursor Molarities by Silar Method

Abstract

INTRODUCTIONNanostructured materials have drawn attentions to the researchers due to the unique physical and chemical properties of nanomaterials, which are different from those of either the bulk materials or single atoms [1]. The reduction of the size of materials causes a deviation of their physical and chemical properties from the bulk and such resultant materials (nanoparticles) are known to possess potential applications and novel properties [2]. Among the different metal oxide films, CdO is an important n-type semiconductor with a cubic structure, which belongs to the II-VI group, with a direct band gap of 2.5 eV and indirect band gap 1.98 eV [3] Nanostructured cadmium oxide thin films have been synthesized onto suitably cleaned glass substrates by SILAR (successive ionic layer adsorption and reaction) method. X-ray diffraction study confirms the formation of nanocrystalline cubic phase of cadmium oxide in the films. Lattice constant is determined using Nelson Riley plots. Using X-ray broadening, crystallite sizes, lattice strain, stress and energy density were studied by using Williamson-Hall method and modified Williamson-Hall method. From literature review, it is seen that a number of researchers have applied these two methods for structural characterization of thin films of different nanocrystals, but till now modified Williamson-Hall method has not been used for CdO nanocrystals. Hence, we have used these methods for structural characterization of deposited CdO thin films. The ultra-high resolution transmission electron microscopic (UHRTEM) study shows that the shape of the particles is nearly spherical and the average particle size agrees well with the result obtained from X-ray diffraction study. Selected area electron diffraction patterns have also supported the formation of cubic phase of cadmium oxide.

تحسين الخصائص الهيكلية لأغشية رقيقة للجسيمات CdO النانوية كدالة الى درجة الحرارة

“…Whereas, the orientation (111) is more prominent with strong, sharp intensity and the higher value it has compared to other peaks because the film surface density energy for this direction is less than the energies of other crystal directions. [3,13,16] Figure 1: XRD analysis of the CdO nanoparticles films for all samples.…”

Synthesis and Fabrication of In2O3: CdO Nanoparticles for NO2 Gas Sensor

“…The possibility of changing some of semiconductor materials properties (such as electrical and structural properties) by doping, making a mixture of them or making then in nanosized shapes has made them very important in many an application of general rules to particular cases such as in solar cells (1,2), optoelectronics (3)(4)(5), spintronic (6), piezoelectric and gas sensors (7)(8) .There have also been studies showing that when semiconductors are exposed to some gases, lead to change their electrical properties. This phenomenon is used in the application of gas sensing (9)(10)(11).…”