Facile synthesis of single crystalline gold nanoplates and SERS investigations of 4-aminothiophenol

Abstract

Single crystalline gold nanoplates with micrometer-scale sizes that are tens of nanometers in thickness were synthesized by reducing HAuCl4 with the disodium salt of ethylenediaminetetraacetic acid (Na2EDTA) in the presence of hexadecyltrimethylammonium bromide (CTAB) in aqueous solution. The results indicated that CTAB plays an important role in the formation of single crystalline gold nanoplates. The application of the as-prepared nanoplates in surface-enhanced Raman spectroscopy (SERS) was investigated by using 4-aminothiophenol (PATP) as probe molecules. As a result of the sharp corners and edges in their shape, the resultant Au nanoplates exhibit excellent Raman enhancement ability. It was found that PATP can be oxidatively transformed into 4,4′-dimercaptoazobenzene on the surface of Au nanoplates during the SERS measurement.