Sonochemical synthesis of core/Shell structured CdS/TiO₂ nanocrystals composites

Abstract

A simple sonochemical route for the surface coating of titanium dioxide on cadmium sulfide nanocrystal was reported. After 2 h ultrasonic irradiation treatment, the mixture of CdS nanocrystals and tetrabutyl titanate in an aqueous medium yielded CdS/TiO₂ nanocrystals composites with core/shell structure. The thickness of TiO₂ layer with smooth interface could be easily controlled via changing the concentration of the precursors and the time of irradiation. The core/shell nanocrysrals were characterized by X-ray diffraction, transmission electron microscope and UV-vis spectrometry techniques. The prepared semiconductor composites with particular band structure present appealing properties especially in photochemical activity.

Keywords

core/shell / CdS/TiO₂ / sonochemical / photochemical activity

References

[1] Lin H. M., Chen Y. L., Yang J., . Synthesis and Characterization of Core/Shell GaP/GaN and GaN/GaP Nanowires[J]. Nano Lett., 2003, 3(4): 537-541.

[2] Yoffe A. D. Semiconductor Quantum Dots and Related Systems: Electronic, Optical, Luminescence and Related Properties of Low Dimensional Systems[J]. Adv. Phys., 2001, 50(1): 1-208.

[3] Breen M. L., Dinsmore A. D., Pink R. H., . Sonochemically Produced ZnS-coated Polystyrene Core-shell Particles for Use in Photonic Crystals[J]. Langmuir, 2001, 17(3): 903-907.

[4] Kang M. G., Han E. H., Kim K. J. Enhanced Photodecomposition of 4-chlorophenol in Aqueous Solution by Deposition of CdS on TiO₂[J]. J. Phtochem. Photobio. A, 1999, 125(1–3): 119-125.

[5] Das K., De S. K. Optical Properties of the Type-II Core-shell TiO₂/CdS Nanorods for Photovoltaic Applications[J]. J. Phys. Chem. C., 2009, 113(9): 3494-3501.

[6] Cao J., Sun J. Z., Li H. Y., . A Facile Room-temperature Chemical Reduction Method to TiO₂/CdS Core/sheath Heterostructure Nanowires[J]. J. Mater. Chem., 2004, 14(7): 1203-1206.

[7] Jia H. M., Xu H., Hu Y., . TiO₂/CdS Core-shell Nanorods Films: Fabrication and Dramatically Enhanced Photoelectrochemical Properties[J]. Electrochemistry Communications, 2007, 9(3): 354-360.

[8] Wang Z. X., Chen J. F., Xue X., . Synthesis of Monodispersed CdS Nanoballs through γ-irradiation Route and Building Core-shell Structure CdS/SiO₂[J]. Mater. Res. Bull., 2007, 42(12): 2211-2218.

[9] Mdleleni M. M., Hyeon T., Suslick K. S. Sonochemical Synthesis of Nanostructured Molybdenum Sulfide[J]. J. Am. Chem. Soc., 1998, 120(24): 6189-6190.

[10] Flint E. B., Suslick K. S. The Temperature of Cavitation[J]. Science, 1991, 253(5026): 1397-1399.

[11] Dhas N. A., Ekhtiarzadeh A., Suslick K. S. Sonochemical Preparation of Supported Hydrodesulfurization Catalysts[J]. J. Am. Chem. Soc., 2001, 123(34): 8310-8316.

[12] Dhas N. A., Suslick K. S. Sonochemical Preparation of Hollow Nanospheres and Hollow Nanocrystals[J]. J. Am. Chem. Soc., 2005, 127(8): 2368-2369.

[13] Doktycz J. S., Suslick K. S. Interparticle Collisions Driven by Ultrasound[J]. Science, 1990, 247(4946): 1067-1069.

[14] Wang Z. Y., Chen J. X., Zhang F., . Synthesis of Core/Shell Type CdS/TiO₂[J]. Rare. Metal. Mat. Eng. S2, 2008, 37: 330-333.

[15] Kim Y. I., Atherton S., Brigham E. S., . Sensitized Layered Metal Oxide Semiconductor Particles for Photochemical Hydrogen Evolution from Nonsacrificial Electron Donors[J]. J. Phys. Chem., 1993, 97(45): 11802-11810.

[16] Hoffmann M. R., Martin S. T., Choi W., . Environmental Applications of Semiconductor Photocatalysis[J]. Chem. Rev., 1995, 95(1): 69-96.