Tuyển tập các báo cáo nghiên cứu khoa học ngành toán học được đăng trên tạp chí toán học quốc tế đề tài: Selective preparation of zero- and onedimensional gold nanostructures in a TiO2 nanocrystal-containing photoactive mesoporous template | Kawamura et al. Nanoscale Research Letters 2012 7 27 http content 7 1 27 o Nanoscale Research Letters a SpringerOpen Journal NANO EXPRESS Open Access Selective preparation of zero- and onedimensional gold nanostructures in a TiO2 nanocrystal-containing photoactive mesoporous template Go Kawamura1 Teruhisa Okuno2 Hiroyuki Muto1 2 and Atsunori Matsuda1 2 Abstract Nanocrystallized SiO2-TiO2 with tubular mesopores was prepared via the sol-gel technique. Gold was deposited in the tubular mesopores of the nanocrystallized SiO2-TiO2. The shape of the gold was varied from one-dimensional 1-D to zero-dimensional 0-D nanostructures by an increase in TiO2 content and ultraviolet UV irradiation during gold deposition. 1-D gold nanostructures GNSs were mainly obtained in the mesopores when a small amount of TiO2-containing mesoporous SiO2-TiO2 was used as a template whereas the use of a template containing a large amount of TiO2 led to the formation of shorter 1-D or 0-D GNSs. UV irradiation also resulted in the formation of 0D GNSs. PACS sample preparation nanowires chemical synthesis methods . Keywords mesoporous titania template gold nanostructures shape control photocatalysis surface plasmon resonance Introduction Gold nanostructures GNSs have been attracting much attention because of the high chemical stability coincident with their unique optoelectronic properties which are dependent on the morphology of the GNSs 1-4 . Surface plasmon resonance SPR is one of the most interesting properties of one-dimensional 1-D GNSs 2-5 . The wavelength of SPR is affected by the length diameter and aspect ratio of the 1-D GNSs 6 7 . Aligned GNSs perform polarization of light 8-10 . Such multifunctionality of the 1-D GNSs opens up new application fields such as wavelength-sensitive nonlinear optical devices and polarization filters 8 9 11 . Several methods for synthesizing GNSs including 1-D GNSs have been reported. These methods include
