Preparation and characterization of hybrid platinum/Prussian blue nanoparticles

Colloidal dispersions of hybrid nanoparticles composed of Prussian blue (PB) and platinum (Pt) were prepared by adding K4FeCN6 and K2PtCl6 in turn into PB colloid solution, in which Pt ion and [FeCN6]4− in an aqueous solution were reduced and oxidized separately. The formation of hybrid platinum/Prussian blue (Pt/PB) nanoparticles was characterized by UV–vis spectrophotometry and transmission electron microscopy (TEM). The diameter of obtained Pt/PB nanoparticles is about 20 nm. The characteristic absorbance peaks of PB nanoparticles at 720 nm could be observed from the Pt/PB colloid. However, the peak magnitude decreases compared with that of PB, which means that Pt covers partly PB nanoparticles. The self-assembled 1,3-propanedithiol was employed to anchor the metal-modified PB nanoparticles on Au electrodes by the strong metal–sulfur interactions. The study of electrochemical cyclic voltammetry shows that PB or Pt of Pt/PB is involved in electrochemical catalytically reduction of oxygen.