title: High-Yield Synthesis of Hollow Octahedral Silver Nanocages with Controllable Pack Density and Their High-Performance Sers Application.
abstract: Nanoparticle-assembled octahedral Ag nanocages with sharp edges have been successfully synthesized through a Cu2O-based template-assisted strategy. In the reaction system, Ag nanoparticles can be self-assembled on the surface of Cu2O octahedrons, which is accomplished by the reduction of Ag+by NaBH4in the presence of sodium citrate as a capping agent. The hollow octahedral Ag nanocages are obtained after removing the inner Cu2O 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 10-14m 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.
authors.affiliation: School of Chemistry and Environment, Beihang University, Beijing, 100191, P. R. China.
authors.forename: Fengqin
authors.initials: F
authors.lastname: Huang
authors.affiliation: School of Chemistry and Environment, Beihang University, Beijing, 100191, P. R. China.
authors.forename: Guanshui
authors.initials: G
authors.lastname: Ma
authors.affiliation: School of Chemistry and Environment, Beihang University, Beijing, 100191, P. R. China.
authors.forename: Juzhe
authors.initials: J
authors.lastname: Liu
authors.affiliation: School of Chemistry and Environment, Beihang University, Beijing, 100191, P. R. China.
authors.forename: Jie
authors.initials: J
authors.lastname: Lin
authors.affiliation: School of Chemistry and Environment, Beihang University, Beijing, 100191, P. R. China. windforcewangxt@gmail.com.
authors.forename: Xiaotian
authors.initials: X
authors.lastname: Wang
authors.affiliation: School of Chemistry and Environment, Beihang University, Beijing, 100191, P. R. China. guolin@buaa.edu.cn.
authors.forename: Lin
authors.initials: L
authors.lastname: Guo
keywords: hollow; nanocages; octahedral Ag cages; pack density; particle distance