Polyol synthesis of silver nanoplates: The crystal growth mechanism based on a rivalrous adsorption

A polyol reducing approach has been applied to synthesize silver nanoplates with an average thickness of 50 nm and edge length of 3 μm in the presence of poly (vinylpyrrolidone) (PVP) and HNO3. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscropy (TEM), and electron diffraction are used to characterize these silver nanoplates. Findings indicate that the nanoplates are single crystals and with their basal plane as (1 1 1) lattice plane. On the basis of the results from thermogravimetric analysis (TG), Fourier transform infrared spectroscopy (FT-IR) and Raman spectroscopy, a crystal growth mechanism based on the rivalrous adsorption between PVP and CN− ions on the surface of silver nanoplates is supposed to explain the crystal anisotropic growth.

► Silver nanoplates have been successfully synthesized by polyol reduction in the presence of poly (vinylpyrrolidone) (PVP) and HNO3.
► Due to the discovery of CN− ions in the solution, a mechanism for the anisotropic growth of silver nanoplates is systematically discussed.
► TG, FT-IR and SERS were used to provide some direct evidences of rivalrous adsorption between PVP and CN− ions on the surface of the silver crystals.