Shape-controlled synthesis of silver nanocrystals via γ-irradiation in the presence of poly(vinyl pyrrolidone)

Silver nanocrystals with controlled morphologies were facilely synthesized via γ-irradiation on aqueous solutions containing AgNO₃ and poly(vinyl pyrrolidone)(PVP) by adjusting the adsorption dose. UV-vis spectroscopy, TEM, XRD and X-ray photoelectron spectroscopy were used to characterize these silver nanocrystals. Spherical silver nanoparticles with diameter of ∼20 nm were formed irradiated by γ-ray with dose of 12 kGy, and one-dimensional silver nanowires with average diameter of 30 nm and length up to 20-30 μm were obtained with dose increased to 36 kGy. In this process, γ-ray and PVP have synergistic effects on the formation of silver nanocrystals, leading to the formation of highly pure phase, as well as a uniform size of each structure.