Controlling the synthesis of silver nanostructures for plasmonic applications.

The symbols and special characters used in the original abstract could not be transcribed due to technical problems. Please use the PDF version to read the abstract. Silver nanostructures have been paid significant attentions in many applications due to their unique physical and chemical properties, which the bulk material does not possess. Controlling Ag nanostructures’ size and shape to define their unique plasmonic features is important for practical applications. Generally, Ag nanostructures could be obtained through two main approaches, chemical and physical methods. Chemical method is the most widely used synthesis technique. That involves creation of Ag atoms from precursors by reduction and subsequent their growth into nanostructures with an aid of a stabilizer. Ag nanostructures with various well- controlled morphologies and sizes have been obtained from the solution phase. The size- and shape-dependent plasmonic features of Ag nanostructures have led to their wide applications in many fields, such as surface enhanced spectroscopy for sensors, catalysis and biological labeling. Driven by potential applications, the work performed in this thesis centers on the synthesis and properties of Ag nanostructures. In the first part, synthesis and characterization of one dimensional (1D) Ag nanostructures were performed. To do so, two kinds of 1D silver nanostructures, silver ‘nanorice’ structures and ‘nanocarrot’ structures were synthesized through a facile polyol method. Polyethylene glycol 600 was used as a solvent and as a reducing agent, and polyvinylpyrrolidone (PVP) worked as capping agent. The main factor leading to the different morphologies of products is that the precursor of silver nitrate AgNO3 was used for synthesis of silver nanorice structures while silver trifluoroacetate CF3COOAg for nanocarrot structures. Their structure details were characterized by transmission electron microscopy and X-ray diffraction. The optical properties were characterized b