A Rapid Synthesis of Oriented Palladium Nanoparticles by UV Irradiation.

Palladium nanoparticles of average size around 8 nm have been synthesized rapidly by UV irradiation of mixture of palladium chloride and potassium oxalate solutions. A rod-shaped palladium oxalate complex has been observed as an intermediate. In the absence of potassium oxalate, no Pd nanoparticles have been observed. The synthesized Pd nanoparticles have been characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), selective area electron diffraction and energy dispersive analysis by X-rays (EDAX) analyses. XRD analysis indicates the preferential orientation of catalytically active {111} planes in Pd nanoparticles. A plausible mechanism has been proposed for the formation of anisotropic Pd nanoparticles.