The effect of number of SILAR cycles on morphological, optical and photo catalytic properties of cadmium sulfide–titania films

Abstract

In this paper, cadmium sulfide-titania nanocomposites were successfully synthesized by electrochemical anodizing and successive ionic layer adsorption and reaction (SILAR) methods. Cadmium sulfide was successfully deposited on titania nanotubes with tunable loading amounts by controlling deposition cycles of SILAR. The morphology, crystal structure, elemental composition and light absorption capability of samples were characterized by FE-SEM, XRD, EDX and UV-Vis methods. Titania nanotubes with 90-220 nm in diameter and 15-30 nm in wall thickness were prepared by one-step anodizing method and then cadmium sulfide deposited onto titania to form cadmium sulfide-titania heterostructure. Characterization of the cadmium sulfide-titania sample indicated that the number of SILAR cycles significantly influenced the morphology and photo catalytic activity of fabricated films. Rh B and MO were adopted as the model dyes and the photo catalytic tests were carried out in detail. Results showed that the photo catalytic activity of cadmium sulfide-titania samples is higher than that with bare titania sample. The incorporation of cadmium sulfide on titania improves the photo catalytic activity due to the synergetic effect. The photo catalytic activity increase with the proper increase of cadmium sulfide amount; however, the activity decreases when the amount of cadmium sulfide is further increased which may result in the formation of the compact films on the surface and a decrease in surface area of samples.Cadmium sulfide-titania sample prepared by SILAR deposition with 5 cycles gives the highest degrading rate, which can be attributed to appropriate cadmium sulfide content. Cadmium sulfide-titania is easy to be recycled and has good stability for repeated use. A mechanism is also studied and an electron transfer route is provided and accounts for the enhanced photo catalytic activity. With the improved visible light degradation performance, cadmium sulfide-titania samples would be expected to be used in water purification.

Multifunctional CdSNPs@ZIF-8: Potential Antibacterial Agent against GFP-Expressing Escherichia coli and Staphylococcus aureus and Efficient Photocatalyst for Degradation of Methylene Blue

“…In recent years, much effort has been devoted to encapsulate nanoparticles (NPs) of metals, − metal oxides, − metal oxide composites, − organic polymers, , polyoxometalates, , and MOFs , into MOFs to form hybrid core–shell composites/structures. These hybrid core–shell materials possess not only the intrinsic properties of the NPs and MOFs but also synergistic properties that explore their more new applications (Table ) in various fields, such as selective photocatalysis/catalysis, − ,,,,, therapy, , and gas storage and sensing , and as supercapacitors and carriers for electrode materials. , NPs@MOFs core–shell composites have been prepared either by using MOFs as templates to generate and embed nanoparticles within their cavities − or by encapsulating presynthesized nanoparticles stabilized with certain surfactants, capping agents, or even ions, ,,,− and usually it has been observed that nanoparticles do not occupy the MOF cavities (because their hydrodynamic radius is much larger than the size of cavity of MOFs), but instead are surrounded by grown MOF particles.…”

Iron–tungsten/titania nanotube films for photoelectrochemical water splitting

“…Distilled water was used to prepare all the aqueous solutions. TiO 2 nanotubes were prepared by anodisation of titanium sheets in ethylene glycol electrolyte containing NH 4 F and water at 60 V for 6 h in a two-electrode configuration using a graphite plate as the cathode electrode [22]. TiO 2 nanotube/Ti samples were then rinsed with distilled water and air dried.…”

Performance of CdS/TNTAs Nanocomposite in Removing Ciprofloxacin and Hydrogen Production using Simultaneously Electrocoagulation-Photocatalysis Process

“…Furthermore, the plate was immersed in a solution of S 2− for 5 minutes and rinsed with water to remove excess S 2− , thereby completing a single SILAR deposition cycle. This process was repeated for six cycles based on the study of the optimal conditions for the synthesis of CdS/TiO2 nanocomposites [24]. By varying the concentration of the precursors using composite values of 0 M, 0.05 M, 0.1 M, and 0.2 M, composite samples with different CdS contents were obtained and denoted as T, CT 0.05, CT 0.1, and CT 0.2, respectively.…”