Morphology-controlled synthesis of silver nanostructures via a solvothermal method

Silver nanostructures have been synthesized by a simple solvothermal method in the presence of poly(vinylpyrrolidone) (PVP). Typically, different exotic agents (NaOH, KBr, NaCl) are added into the reaction system. The anions (OH⁻, Cl⁻, Br⁻) from these agents can combine Ag⁺ to form silver salt colloids (AgOH, AgBr and AgCl), decreasing the concentration of free Ag⁺ in the initial formation of silver seeds. However, different release rates of Ag⁺ from these colloids to the solution in the subsequent reaction may play different roles in the growth of silver seeds. The as-prepared silver nanostructures were characterized by UV–vis absorption spectrum, X-ray diffraction (XRD) and field emission scanning electron microscope (FSEM). It is found that silver nanostructures with various shapes can be obtained by the addition of different exotic agents. Finally, our work provides a simple route to synthesize silver nanostructures with controllable morphologies.