Rich Capping Ligand-Ag Colloid Interactions

Ag cubes, plates, and irregular particles were acquired by the reduction of AgNO3 respectively in poly(vinylpyrrolidone) (PVP) and ethylene glycol, PVP and dimethylformamide (DMF), and DMF. The surface adsorbates on various Ag colloids were studied with X-ray photoelectron spectroscopy, infrared spectroscopy, and Raman spectroscopy. PVP adsorbs on Ag cubes via its N and O atoms with charge transferring from PVP to Ag. DMF adsorbs on irregular Ag particles in two configurations with charge transferring from Ag to DMF. One adsorbs via the N atom, and the other adsorbs via the N and O atoms. PVP adsorbs on Ag plates via the N atoms with charge transferring from PVP to Ag, whereas DMF adsorbs on Ag plates via the N and O atoms with charge transferring from Ag to DMF. These results reveal rich capping ligand Ag colloid interactions that will strongly affect the surface chemistry and surface-mediated properties of Ag colloids.