Morphology-controlled synthesis of monodisperse silver spheres via a solvothermal method

Monodisperse silver spheres were successfully synthesized by a solvothermal method with the assistance of polyvinylpyrrolidone (PVP). The final products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), laser particle size analyzer, transmission electron microscopy (TEM), Fourier transform infrared spectrophotometer (FTIR), and UV–vis absorption spectroscopy. The as-synthesized silver spheres with cubic phase structure were nearly monodisperse and had an average diameter of 250 nm. The experimental results showed that their sizes and morphologies could be tailored by changing the reaction temperature, time, and PVP concentration under solvothermal conditions. The optical properties of silver spheres were investigated as a function of PVP concentration. A possible mechanism was presented for the formation of monodisperse silver spheres.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideResearch highlights► Silver spheres synthesized by a solvothermal method with the polyvinylpyrrolidone. ► The spheres are monodisperse and have an average diameter of 250 nm. ► Silver spheres could be readily controlled by the concentration of PVP. ► The growth involves an initial stage, single-crystal seeds and twinned seeds.