Optical, structural and morphological properties of silver nanoparticles and its influence on the photocatalytic activity of TiO2.

Silver nanoparticles (Ag NPs) were synthesized by solution combustion method using glycine and citric acid as fuels. The prepared Ag NPs were characterized by optical absorption spectroscopy, X-Ray Diffraction (XRD), High Resolution Transmission Electron Microscopy (HRTEM), Fourier Transform Infrared spectroscopy (FTIR) and Energy Dispersion Spectroscopic (EDS) techniques. Surface plasmon resonance peak was appeared at 410 and 418 nm for glycine (GAg) and citric acid (CAg) assisted silver nanoparticles respectively. The silver NPs are fcc in crystal structure. The calculated average particle size from XRD was found around 29 nm for GAg and 41 nm for CAg. HRTEM image shows that the silver nanoparticles have strain and fivefold symmetry formed by twinning in the crystal structure. The photocatalytic activity of TiO2 nanoparticles with Ag NPs were also elucidated and were found that the Ag NPs enhance the photocatalytic activity of TiO2.