Well-dispersed M@TiO_(2)(M=Ag,Pd,Au,Pt)nanocomposite particles with a diameter of 200-400 nm can be synthesized on a large scale by a clean photochemical route which does not require any additives using spherical ruti...Well-dispersed M@TiO_(2)(M=Ag,Pd,Au,Pt)nanocomposite particles with a diameter of 200-400 nm can be synthesized on a large scale by a clean photochemical route which does not require any additives using spherical rutile nanoparticles as a support.The sizes of Pt,Au,and Pd nanoparticles formed on the surface of TiO_(2) particles are about 1 nm,5 nm,and 5 nm,respectively,and the diameter of Ag nanoparticles is in the range 2-20 nm.Moreover,the noble metal nanoparticles have good dispersity on the particles of the TiO_(2) support,resulting in excellent catalytic activities.Complete conversion in catalytic CO oxidation is reached at temperatures as low as 333 and 363 K,respectively,for Pt@TiO_(2) and Pd@TiO_(2) catalysts.In addition,the antibacterial effects of the as-synthesized TiO_(2) nanoparticles,silver nanoparticles,and Au@TiO_(2) and Ag@TiO_(2) nanocomposites have been tested against Gram-negative Escherichia coli(E.coli)bacteria.The results demonstrate that the presence of the TiO_(2) matrix enhances the antibacterial effect of silver nanoparticles,and the growth of E.coli can be completely inhibited even if the concentration of Ag in Ag@TiO_(2) nanocomposite is very low(10μg/mL).展开更多
基金S.-H.Yu acknowledges the funding support from the National Basic Research Program of China(No.2010CB934700)the Program of International S&T Cooperation(No.2010GR0314)+1 种基金the National Science Foundation of China(NSFC)(Nos.50732006,20671085)and the Partner-Group of the Chinese Academy of Sciences&the Max Planck Society.S.F.Chen thanks the Innovation Fund for Graduate Students of USTC(2006)for support.
文摘Well-dispersed M@TiO_(2)(M=Ag,Pd,Au,Pt)nanocomposite particles with a diameter of 200-400 nm can be synthesized on a large scale by a clean photochemical route which does not require any additives using spherical rutile nanoparticles as a support.The sizes of Pt,Au,and Pd nanoparticles formed on the surface of TiO_(2) particles are about 1 nm,5 nm,and 5 nm,respectively,and the diameter of Ag nanoparticles is in the range 2-20 nm.Moreover,the noble metal nanoparticles have good dispersity on the particles of the TiO_(2) support,resulting in excellent catalytic activities.Complete conversion in catalytic CO oxidation is reached at temperatures as low as 333 and 363 K,respectively,for Pt@TiO_(2) and Pd@TiO_(2) catalysts.In addition,the antibacterial effects of the as-synthesized TiO_(2) nanoparticles,silver nanoparticles,and Au@TiO_(2) and Ag@TiO_(2) nanocomposites have been tested against Gram-negative Escherichia coli(E.coli)bacteria.The results demonstrate that the presence of the TiO_(2) matrix enhances the antibacterial effect of silver nanoparticles,and the growth of E.coli can be completely inhibited even if the concentration of Ag in Ag@TiO_(2) nanocomposite is very low(10μg/mL).
