title: Formation of Ag nanoframes with facilitation of dithiols.
abstract: Two-dimensional Ag nanoprisms readily formed Ag triangular nanoframes upon electron beam irradiation. Following meso-2, 3-dimercaptosuccinicacid (DMSA) ripening behavior, continuous electron beam exposure transformed a solid nanoplate into a core/void/shell morphology, which then evolved into a hollow nanoframe structure. TEM was used to observe the ripening and etching processes of Ag nanoprisms as a function of DMSA concentration and electron irradiation time. X-ray diffraction (XRD) and FT-IR analysis were conducted to characterize the Ag nanoprism structure and surface before and after treatment with DMSA. X-ray photoelectron spectroscopy (XPS) was used to determine surface chemical compositions and indicated DMSA was adsorbed on the Ag nanoprisms in the form of Ag(+)-S(-). Raman measurements provided evidence of a disulfide group on Ag nanoprisms. Similar organosulfur structures such as mercaptosuccinic acid and 2-mercaptoacetic acid were also studied with results suggesting that the two S-H groups of dithiol DMSA played the crucial role in nanoframe fabrication. Using the same strategy with DMSA, the nano-architecture can be extended to 2D nanodiscs yielding nanorings.
authors: Institute of Oral Medicine, National Cheng Kung University, Tainan 701, Taiwan.
authors: Fong-Yu
authors: FY
authors: Cheng
authors: Kuo-Wei
authors: KW
authors: Hu
authors: Chen-Sheng
authors: CS
authors: Yeh
mesh_terms: D046529:Microscopy, Electron, Transmission; D049329:Nanostructures; D056951:Photoelectron Spectroscopy; D012834:Silver / Q000737:chemistry*; D013438:Sulfhydryl Compounds / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D013438:Sulfhydryl Compounds; D012834:Silver