High‐Yield Synthesis of Hollow Octahedral Silver Nanocages with Controllable Pack Density and Their High‐Performance Sers Application. Issue 39 (23rd August 2016)

• Record Type: Journal Article
• Authors: Huang, Fengqin; Ma, Guanshui; Liu, Juzhe; Lin, Jie; Wang, Xiaotian; Guo, Lin
• Is Part Of: Small. Volume 12:Issue 39(2016)
• Page Start: 5442
• Page End: 5448
• Publication Date: 2016-08-23
• Subjects: hollow -- octahedral Ag cages -- pack density -- particle distance -- nanocages; Nanotechnology -- Periodicals; Nanoparticles -- Periodicals; Microtechnology -- Periodicals; 620.5
• DOI: 10.1002/smll.201602280
• Languages: English
• ISSNs: 1613-6810

Abstract

Abstract : Nanoparticle‐assembled octahedral Ag nanocages with sharp edges have been successfully synthesized through a Cu2 O‐based template‐assisted strategy. In the reaction system, Ag nanoparticles can be self‐assembled on the surface of Cu2 O octahedrons, which is accomplished by the reduction of Ag + by NaBH4 in the presence of sodium citrate as a capping agent. The hollow octahedral Ag nanocages are obtained after removing the inner Cu2 O cores with acetic acid. According to the scanning electron microscopy (SEM) and transmission electron microscopy characterization, the Ag nanocages are weaved by small nanoparticles, the rough surfaces are bestrewed with pores and sharp edges. It is found that the pack density of Ag nanoparticles strongly affects the surface enhanced Raman scattering (SERS) activities. The as‐prepared 1.05‐Ag cages with optimal pack density have suitable interparticle distance and suitable size of pores, which significantly enhance SERS signals. The SERS signals of rhodamine 6G (R6G) molecules can be detected at an ultralow concentration of 10 −14 m when 1.05‐Ag cages are used as substrates. In addition to sensitivity, 1.05‐Ag cages also exhibit good reproducibility. It is expected that the ultrahigh sensitivity will endow the Ag nanocages to become a promising candidate as high‐performance SERS‐based chemical sensor. Abstract : Octahedral Ag nanocages with sharp edges with suitable pack density are prepared and used as a highly sensitive surface enhanced Raman scattering substrate for detecting R6G. The Cu2 O‐based templating strategy to prepare Ag nanocages is facile, efficient, and productive. The as‐prepared 1.05‐Ag cage can detect typical R6G Raman peaks even at an ultralow concentration of 1 × 10 −14 m and show very good reproducibility.