Ag_2S nanoparticle nanowires were prepared in a porous anodic aluminum oxide template by a simple paired cell method,and were characterized by XRD,FESEM,HRTEM and EDS.The results showed that the as-prepared nanowires were composed of monoclinic Ag_2S nanoparticles.The nanowire diameters ranged from 165 to 270 nm,and Ag_2S nanoparticles were nearly spherical with diameters of 40 to 60 nm.The paired cell method is simple,low cost and easy to control for the fabrication of high density and high aspect ratio Ag_2S nanoparticle nanowires.A formation mechanism for the nanoparticle nanowires was suggested.
LI XiaoNing YANG XiuChun HAN ShanShan LU Wei HOU JunWei LIU Yan
Ag nanoparticles embedded in soda-lime silicate glass were fabricated by ion-exchange and subsequently annealing method. Effects of annealing duration on the optical nonlinearity and ultrafast dynamics of Ag nanoparticles in glass were investigated by z-scan technique and pump-probe technique. The results indicate that the third-order optical nonlinearity increases with extending the annealing time, the fast decay process with lifetime of a few picoseconds is attributed to thermal equilibrium process of hot electrons and the energy transfer to lattices by interaction with phonons in the formed Ag nanoparticles, while the slow decay in more than one hundred picoseconds corresponds to the subsequent cooling process by a thermal diffusion from the Ag nanoparticle to the host matrix via the phonon-medium interaction. The fast decay process is accelerated with extending the annealing time.
