Selective Detection of Mercury (II) by Etching the Corners of Silver Triangular Nanoplates

Abstract

ABSTRACT As confirmed by transmission electron microscopy, we found that Hg2+ has good affinity to etch the sharp corners of silver triangular nanoplates. The etching process induced an apparent absorption peak shift of silver triangular nanoplates from 580 to 530 nm. The shift degree of the absorption peak has a good linear relationship with the amount of Hg2+ added; thus, Hg2+ with a concentration from 0.2 to 1.5 µM can be quantitatively detected by measuring silver triangular absorption. The interaction between mercury and silver triangular nanoplates proposed here is also a new example of silver triangular nanoplate etching and important for explaining the etching mechanism.