Formation mechanism of CdxZn1-xS/PVA nanocomposites by SILAR method

• Published in: Results in physics 2020-09, Vol.18, p.103280, Article 103280
• Main Authors: Muradov, Mustafa Bayram, Gahramanli, Lala Rasim, Balayeva, Ofeliya Oqtay, Nasibov, Ilyas Namaz, Eyvazova, Goncha Malik, Amiraslanov, Imameddin Rajabali, Aghamaliyev, Zoxrab Adalat
• Format: Article
• Language: English
• Subjects: CdxZn1-xS nanoparticles; Nanocomposites; Polyvinyl alcohol (PVA); SILAR method; Thin films
• ISSN: 2211-3797; 2211-3797
• DOI: 10.1016/j.rinp.2020.103280

•The change in the ratio of Cd2+/Zn2+ ions in a crystallization medium leads to a change in the chemical composition of particles CdxZn1-xS.•With increasing Cd2+/Zn2+ ratio decreasing the band gap of nanoparticles CdxZn1-xS.•The chemical composition of the obtained nanoparticles CdxZn1-xS by joint sorption of cations also depends on the type of sorption centers on which they are formed.•The heterogeneous distribution of nanoparticles over the thickness of the films is explained with the difference in the energy state of the nanoparticles in the surface region and inside the films. In this study, CdxZn1-xS/PVA nanocomposites have been grown within polyvinyl alcohol (PVA) polymer matrix using the combined sorption of the cations by the successive ionic layer adsorption and reaction (SILAR) method. The effects of the different amount of Cd2+ and Zn2+ ions depending on the × value in CdxZn1-xS, the number of reaction cycles, various cation sources, and the different reaction parameters on the formation mechanism and physical and chemical properties of nanomaterials were studied in this paper. The structural, optical analysis, chemical composition determination, morphology and the distribution of nanoparticles on the surface are characterized and studied using X-ray diffractometer (XRD), ultraviolet–visible (UV–Vis) spectrophotometer, scanning electron microscopy (SEM), energy-dispersive X-ray spectrometer (EDX) and optical microscopy. The particle size of the sample obtained after 5 cycles is larger than the particle size obtained at 2 cycles. The formation speed of nanoparticles is weak at room temperature and the particle size is in the range of 6.63–9.66 nm after 2 cycles and 8.89–22.7 nm after 5 cycles by SEM. The optical microscope results show that the distribution of elements by thickness is non-uniformity. The reason for non-uniformity is that the volume and surface energy are different. The band gap value of nanoparticles decreases as increasing the concentration of Cd2+ ions in CdxZn1-xS nanostructures. The decrease in Eg depends on the growth of the particle size. This type of materials have great applications in photovoltaics, solar cells, and markers.