One-step synthesis of Ag@PANI nanocomposites and their application to detection of mercury

The Ag@Polyaniline (PANI) core–shell nanoparticles were successfully synthesized by one-step radiation of sunlight method using silver nitrate as the oxidant for aniline without any additives or templates. The Ag@PANI core–shell nanocomposites were used as active surface enhanced Raman scattering (SERS) nanoprobes for the detection of some heavy metal ions, such as Pb2+, Cu2+ Hg2+, Cd2+, and so on, which is based upon the Raman intensity response of PANI to metal ions. It turns out that the nanoprobes represent a rather high selectivity for Hg2+ detection. It is also important that the detection limit of Hg2+ concentration is ca. 1 × 10−12 M in this system, due to the great sensitivity of SERS nanoprobes. The developed nanoprobes could have potential applications in highly sensitive chemical, environmental and biological analysis, as well as medical detection.