Microwave Assisted Synthesis of Pt_xRu_1−x-NiTiO₃: A Novel Hybrid Nanostructured Electrocatalyst for Direct Methanol Oxidation

Abstract

We have explored the preparation of PtxRu1-x-NiTiO3 hybrid electrocatalysts for the application of methanol oxidization. The X-ray diffraction (XRD) and Raman analysis of PtxRu1-x-NiTiO3 confirmed the rhombohedral crystal structure of NiTiO3 and cubic-structured Pt(Ru) nanoparticles. Transmission electron microscopy (TEM) analysis signifies that Pt(Ru) nanoparticles is decorated on the surface of the NiTiO3. The mean size of the Pt(Ru) nanoparticles calculated from the TEM profile is around 2 nm which corroborates with crystallite size estimated from XRD. X-ray photoelectron spectroscopy analysis confirms the presence of metallic Pt along with its oxidized components (Pt2+ and Pt4+). The cyclic voltammetry analysis evidence that Pt0.5Ru0.5-NiTiO3 has shown better activity in methanol oxidation compared with the other compositions of PtxRu1-x-NiTiO3 along with the maximum current density of 65.41 mA/cm2 with less carbon poisoning. Chronoamperometry and polarization studies represent the stability and electrochemical activity of the Pt0.5Ru0.5-NiTiO3 electrocatalysts towards methanol oxidation. Based on the research carried out in this work, it is concluded that PtxRu1-x-NiTiO3 would be a promising candidate as an electrocatalyst for methanol oxidation in direct methanol fuel cells.