Abstract
Metal nanoframes, especially ultrathin ones, with excellent plasmonic properties are synthetically interesting and highly attractive. Herein we report on the synthesis of Au nanobipyramid-embedded ultrathin metal nanoframes with one of the plasmon modes very similar to that of the Au nanobipyramids. The synthesis is mediated by silver coating on Au nanobipyramids. The excellent plasmonic properties of the Au nanobipyramid-embedded ultrathin metal nanoframes are ascribed to the little influence of the ultrathin metal nanoframes on the Au nanobipyramids, as verified by electrodynamic simulations. The increase in the amount of the added metal atoms changes the nanostructure from the nanoframe to a nanocage shape. The method has also been successfully applied to (Au nanobipyramid)@Ag nanorods with different lengths and Au nanobipyramids with different longitudinal dipolar plasmon wavelengths, suggesting the generality of our approach. We have further shown that the Au nanobipyramid-embedded ultrathin metal nanoframes possess an excellent surface-enhanced Raman scattering and outstanding in situ reaction probing performance. Our study opens up a route for the construction of plasmonic ultrathin metal nanoframes based on Au nanobipyramids for plasmon-enabled applications.
Highlights
Metal nanostructures have attracted enormous interest in a wide range of areas, such as waveguides,[1] optics,[2,3] solar energy harvesting,[4] photocatalysis,[5,6] sensing[7,8] and biomedicine.[9,10] The physicochemical properties of metal nanostructures are well known to be strongly correlated with their size and shape
Because BrÀ ions derived from cetyltrimethylammonium bromide (CTAB) can selectively bind to the side facets, that is, the {100} facets, on the (Au NBP)@Ag nanorods, we argue that these sites will be preferentially activated toward oxidation
The released Ag+ ions should stay soluble by complexing with BrÀ ions to form AgBr2À. Both AgBr2À and the metal complex precursor can be reduced by ascorbic acid to generate Ag and the desired metal atoms, followed by their deposition on the (Au NBP)@Ag nanorods.[45]
Summary
Metal nanostructures have attracted enormous interest in a wide range of areas, such as waveguides,[1] optics,[2,3] solar energy harvesting,[4] photocatalysis,[5,6] sensing[7,8] and biomedicine.[9,10] The physicochemical properties of metal nanostructures are well known to be strongly correlated with their size and shape. The main plasmon wavelengths of the four types of Au NBP-embedded ultrathin metal nanoframes remain approximately the same as that of the Au NBP, with the Pd and Pt ones showing no peaks in the mid-infrared region (Fig. 2d).
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
