In-situ X-ray Absorption Study of Evolution of Oxidation States and Structure of Cobalt in Co and CoPt Bimetallic Nanoparticles (4 nm) under Reducing (H2) and Oxidizing (O2) Environments

摘要: In-situ near edge X-ray absorption fine structure spectroscopy was performed to monitor the oxidation states of Co and CoPt nanoparticles (NPs) 4 nm size in presence H2 O2 pressure range 1 bar 36 Torr respectively. Platinum helps rapid reduction cobalt oxides hydrogen at a rather low temperature (38 °C). In addition, reversible changes NPs as function cycling oxygen (in millitorr Torr) are quantified compared. The role Pt process reducing oxidizing explored. Our findings permit prediction reaction conditions altered. experimental results also suggest tetrahedral Cobalt oxide that differs from Co3O4 spinel structure.