Formation of Platinum (Pt) Nanocluster Coatings on K-OMS-2 Manganese Oxide Membranes by Reactive Spray Deposition Technique (RSDT) for Extended Stability during CO Oxidation

Abstract

Nanocluster formation of a metallic platinum (Pt) coating, on manganese oxide inorganic membranes impregnated with multiwall carbon nanotubes (K-OMS-2/MWCNTs), applied by reactive spray deposition technology (RSDT) is discussed. RSDT applies thin films of Pt nanoclusters on the substrate; the thickness of the film can be easily controlled. The K-OMS-2/MWCNTs fibers were enclosed by the thin film of Pt. X-ray diffraction (XRD), scanning electron microscopy/X-ray energy dispersive spectroscopy (SEM/XEDS), focus ion beam/scanning electron microscopy (FIB/SEM), transmission electron microscopy (TEM), and X-ray 3D micro-tomography (MicroXCT) which have been used to characterize the resultant Pt/K-OMS-2/MWCNTs membrane. The non-destructive characterization technique (MicroXCT) resolves the Pt layer on the upper layer of the composite membrane and also shows that the membrane is composed of sheets superimposed into stacks. The nanostructured coating on the composite membrane material has been evaluated for carbon monoxide (CO) oxidation. The functionalized Pt/K-OMS-2/MWCNTs membranes show excellent conversion (100%) of CO to CO2 at a lower temperature 200˚C compared to the uncoated K-OMS-2/MWCNTs. Moreover, the Pt/K-OMS-2/MWCNTs membranes show outstanding stability, of more than 4 days, for CO oxidation at 200˚C.