Sculpturing effect of chloride ions in shape transformation from triangular to discal silver nanoplates

The sculpturing effect of chloride ions on the shape transformation of silver nanoparticles is presented. UV-vis spectroscopy and transmission electron microscopy (TEM) were used to monitor the evolution of silver nanoplates. Cl- can etch the corners and side faces of the silver nanoprism, and the resulting nanoparticles are disk-like in shape. The dissolved silver atoms would aggregate to form small silver clusters, which were stabilized by the Cl- and citrate ions. The facet-selective etching effect of Cl- is mainly attributed to the surface energy difference of each face of the nanoplate. The thickness of the nanodisk increased during the etching process because of the redeposition of sliver clusters on the {111} planes. The prepared nanodisk also gave rise to high SERS intensity of the probing molecule.