Study of the optical and structural properties of Pt nanoparticles prepared by laser ablation as a function of the applied electric field

Pt NPs have attracted much attention because of their applications in many aspects such as the electronics industry, fuel cells, cancer therapy, etc. The influence of the applied electric field on the formation of platinum NPs by laser (Nd:YAG, lambda = 1064 nm) ablation technique was investigated, for the first time. The TEM images showed that at higher values of the electric field, a variety of shapes like rectangular, hexagon, and rhombic were appeared besides the spherical NPs, as confirmed by SEM investigations. By increasing the applied electric field, the average size of Pt NPs decreased from 20 to 9 nm. In addition, from the XRD spectra, the mean crystalline size, crystal structure, d-spacing, and lattice parameters of NPs were calculated. On the basis of the optical absorption spectra of NPs, we observed a size-dependent blue shift of the SPR peak position when the value of the electric field increased from 0 to 20 V/cm. To identify the stretching and bending frequencies of the molecular functional groups attached to the NPs surface, Raman and FT-IR spectroscopy was applied.