Authors:  M. S. Abd El-sadek

Contact: Nanomaterial Laboratory, Physics Department, Faculty of Science,

South Valley University, Qena-83523, Egypt

*E-mail: mahmoud.abdelsadek@sci.svu.edu.eg, el_sadek_99@yahoo.com

Abstract

Core/shell nanomaterials provide the possibility for enhanced functionality and multifunctional properties in contrast with their more-limited single-component counterparts. One example of these nanomaterials is the inorganic core/shell structure. In the case where semiconductors comprise the core and shell, the core-shell motif has permitted enhanced photoluminescence, improved stability against photochemical oxidation; enhanced processibility, and engineered band structures. Multi-functional CdTe@FeOOH core/shell nanoparticles synthesized by a simple synthetic route called a seed-mediated growth approach [1-3], composed of a fluorescent nanocrystals core, CdTe, and a magnetic metal oxyhydroxides, FeOOH. Initially, the luminescent CdTe nanocrystals were synthesized with bi-functional molecule mercaptoacetic acid (MAA) as a stabilizer and using Na₂TeO₃ as the Te source. The Fe³⁺ in the form of Fe(NO₃)₃.9H₂O was added to CdTe nanocrystals in aqueous solution and slowly hydrolyzed to deposit a layer of oxyhydroxide (FeOOH) onto the luminescent CdTe nanocrysals (as a core) in the presence of stabilizer at pH ≈ 11.2. The effect of refluxing time and the concentration of Fe³⁺ on the preparation of these samples were measured using UV-Visible absorption and photoluminescence analysis. The synthesized CdTe@FeOOH core/shell nanoparticles were characterized with XRD, EDAX, FT-IR, TEM, and thermal analysis. The resulted multi-functional core/shell nanoparticles were water-

soluble and show good optical and magnetic properties. This provides some potential applications, such as simultaneous magnetic resonance imaging and fluorescent imaging, use as catalysts and magnetic-optical materials.

Reference

1-      M. S. Abd El-sadek, J. Ram Kumar, S. Moorthy Babu and M. S. El-hamidy, J. Alloys and Compounds 496 (2010) 589.

2-      M. S. Abd El-sadek, J. Ram Kumar, S. Moorthy Babu and M. S. El-hamidy, Mater. Chem and Phys., 124 (2010) 592.

3-      M. S. Abd El-sadek and S. Moorthy Babu, J. Solid State Chemistry, Vol. 184 (2011) 1135.