A one-step facile synthesis of Ag–Ni core–shell nanoparticles in water-in-oil microemulsions

• Published in: Colloids and surfaces. A, Physicochemical and engineering aspects Vol. 367; no. 1; pp. 96 - 101
• Main Authors: Xia, Lixin, Hu, Xinhu, Kang, Xiaobo, Zhao, Hongping, Sun, Mengtao, Cihen, Xiaowei
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 01.09.2010; Elsevier
• Subjects: Bimetallic nanoparticle; Catalysis; Chemistry; Colloidal state and disperse state; Core–shell structure; Emulsions. Microemulsions. Foams; Exact sciences and technology; General and physical chemistry; Nickel; One-step synthesis; Physical and chemical studies. Granulometry. Electrokinetic phenomena; Silver; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; Silver; Nickel; Core–shell structure; Bimetallic nanoparticle; One-step synthesis; Water; Nanoparticle; Nickel nitrate; X ray; Silver nitrate; Potential; Degradation; Chemical reduction; Synthesis; Photoelectron spectrometry; Core-shell structure; Structure; Catalytic reaction; Transition metal; Nanostructure; X ray diffraction; Heptane; Thickness; Oil; Transmission electron microscopy; Water oil microemulsion; Sodium; Morphology; Preparation
• ISSN: 0927-7757; 1873-4359
• DOI: 10.1016/j.colsurfa.2010.06.020

A one-step facile synthesis is devised for preparation of well-dispersed Ag–Ni core–shell nanoparticles with uniform and intact shells. The process is performed by a reduction of silver nitrate and nickel nitrate with sodium borohydride in water-in-oil (W/O) microemulsions of water/polyoxyethylene (4) nonylphenol (OP-4) and polyoxyethylene (7) nonylphenol (OP-7)/ n-heptane. Transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and UV–vis absorption are utilized to characterize the Ag–Ni core–shell nanoparticles. Furthermore, the effect of molar ratio of Ni 2+ to Ag + and dosage of Ni 2+ and Ag + on morphology of the core–shell nanostructure is also discussed in detail. The thickness of Ni layers on the surface of Ag nanoparticles could be controlled by the dosage of Ni 2+ and Ag +. The Ag–Ni core–shell nanoparticles showed a high catalytic activity for degradation reaction of eosin Y. The product may also have many potential applications in optical, magnetic, biochemical, and biomedical fields. The synthetic method reported here suggests a very promising route for the preparation of bimetallic core–shell structures, which is a subject of intense interest.