Nano Sized TiO₂ Decorated with Metal Nanoparticles produced by Sodium Borohydride Reduction

This approach focuses on simple technique of synthesizing nano sized TiO₂ coated metal nanoparticles without any template or stabilizer. TiO₂ nanoparticles (NPs) with fine particle size are produced by the hydrolysis of Titanium Tetrachloride (TiCl₄) as developed by Rabani et al.¹ The resulting TiO₂-NPs were decorated with metal NPs by the addition of metal precursors and reduction using sodium borohydride (NaBH₄) as reducing agent. TiO₂ plays a versatile role in photocatalysis, photodegradation, radiation chemistry and so forth due to its semiconducting properties. However, the large band gap which needs ultraviolet light for activation is still a barrier in its application part.² Recent trends work on overcoming this issue by decorating TiO₂ with noble metal NPs which can trap the electrons for electron hole separation. In our research study we particularly emphasis on Gold (Au) and Platinum (Pt) metal NPs with TiO₂-NPs in aqueous medium. This present method will have an implications for better enhancement in many catalytic applications like reduction of 4-nitrophenol, mechanistic study of alkyl radical reactions³ etc.

References:

• Ruomei Gao, Agnes Safray, Joseph Rabani, Fundamental reactions in TiO2 nanocrystalline aqueous solutions studied by pulse radiolysis, Radiation Physics and Chemistry 2002, 65, 599-609.
• Tatiana C. Damato, Caio C. S. de Oliveria, Rômulo A. Ando, Pedro H. C. Camargo, A Facile Approach to TiO2 Colloidal Spheres Decorated with Au Nanoparticles Displaying Well-Defined Sizes and Uniform Dispersion, Langmuir 2013, 29, 1642-1649.
• Ronen Bar-Ziv, Tomer Zidki, Israel Zibermann, Guy Yardeni, Dan Meyerstein, Effect of Hydrogen Pretreatment of Platinum Nanoparticles on their Catalytic Properties: Reactions with Alkyl Radicals- A Mechanistic Study, ChemCatChem 2016, 8, 1-5.