writer：Hongxu Chen, Tieqiang Wang, Huaizhong Shen, Wendong Liu, Shuli Wang, Kun Liu, Junhu Zhang, Bai Y
keywords：colloidal lithography, nanoparticle/polymer composites, nanorod, barcode
source：期刊
specific source：Nano Res.
Issue time：2015年
We demonstrate a facile method combining colloidal lithography, selective
ion-exchange, and the in situ reduction of Ag ions (Ag+) for the fabrication
of multi-segmented barcode nanorods. First, polymer multilayer films were
prepared by spin-coating alternating thin films of polystyrene and polyacrylic
acid (PAA), and then multi-segmented polymer nanorods were fabricated via
reactive ion etching with colloidal masks. Second, Ag nanoparticles (Ag NPs)
were incorporated into the PAA segments by an ion exchange and the in situ
reduction of the Ag+. The selective incorporation of the Ag NPs permitted the
modification of the specific bars of the nanorods. Lastly, the Ag NP/polymer
composite nanorods were released from the substrate to form suspensions for
further coding applications. By increasing the number of segments and changing
the length of each segment in the nanorods, the coding capacity of nanorods
was improved. More importantly, this method can easily realize the density
tuning of Ag NPs in different segments of a single nanorod by varying the
composition of the PAA segments. We believe that numerous other coded
materials can also be obtained, which introduces new approaches for fabricating
barcoded nanomaterials.