Pt nanoparticles were obtained via the thermal decomposition of (NH 4 ) 2 [PtCl 4 ] (diammonium tetrachloroplatinate) by heating from room temperature to 760°C. The thermal decomposition process was analyzed using thermogravimetric analysis (TGA) and differential thermal analysis (DTA), X-ray thermodiffraction and infrared spectroscopy. The size and structure of the platinum particles were analyzed using transmission electron microscopy (TEM). The electrochemical activity of Pt particles was assessed by cyclic voltammetry in 0.5 M H 2 SO 4 . The TGA and DTA results suggested that the thermal decomposition of the precursor proceeded in two stages: loss of NH 4 Cl at *300°C, followed by loss of NH 4 Cl and Cl 2 at *372°C. Metallic Pt particles were then produced at temperatures of 372°C and above. At 760°C, the mean ± SD size of the Pt particles was (4.1 ± 1.6) nm, as determined from TEM measurements. In cyclic voltammetry (CV) measurements, an electrode comprised of glassy carbon and Pt particles in 0.5 M H 2 SO 4 exhibited behavior similar to that observed using a polycrystalline Pt electrode.
Platinum-tungsten oxides supported on Vulcan carbon were incorporated by means of an impregnation method. XRD and TEM-EDX results indicated that the material is formed by a mixture of tungsten trioxide and platinum particles supported on carbon. XPS analysis showed the presence of tungsten trioxide, metallic platinum and platinum oxides (PtO and PtO 2 ) on the surface of the material. The catalytic performance of PtWO x /C and Pt/C for the oxygen reduction reaction (ORR) was analyzed in the absence and presence of methanol throughout cyclic voltammetry and rotating disk electrode. The results indicated that the addition of tungsten trioxide increases both the catalytic performance of the ORR and catalyst's methanol tolerance.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.