INFLUENCE OF PLATINUM PRECURSOR (H2PTCL6) CONCENTRATION ON THE PLASMONIC PROPERTIES OF AU@PT BIMETALLIC NANOPARTICLES

The deposition of a second metal on the surface of spherical gold nanoparticles allows tuning the nanoparticles’ optical properties, making them multifunctional nanoplatforms. A successive route can be used for this purpose allowing control over the final physicochemical properties of the nanoparticles.(1) We used, the successive route to obtain bimetallic Au@Pt nanoparticles and evaluate the influence of the concentration of H2PtCl6 on the plasmonic properties of spherical gold nanoparticles. Gold core was previously synthesized via the Turkevich method (2), and Au@Pt NPs were prepared from three different Pt/Au molar ratios (0.33, 0.5, and 1, respectively). Through UV-vis spectroscopy that the higher the Pt/Au ratio, the higher the red-shift of the plasmonic band. DLS measurements showed that the hydrodynamic diameter of the nanoparticles is directly related to the increase in the Pt/Au ratio. The morphology of the nanoparticles was obtained through TEM EDS imaging, indicating that the final morphology had a "decorated morphology”. Thus, the results found demonstrated that the concentration of the platinum precursor is directly related to the final physicochemical properties of the bimetallic nanoparticles and can direct them towards possible biomedical applications, such as photothermal treatment.