Morphology-Controlled Fabrication of Co3O4 Catalysts and Performance Towards Low Temperature CO Oxidation

Abstract

This article reports the heterogeneous catalysis of CO oxidation over nanostructured Co3O4 at low temperatures. The hydrothermal method was deftly exploited to fabricate nanostructured Co3O4 with three kinds of precipitants (i.e., urea, hexamethylene tetramine, and sodium hydroxide), which were thoroughly characterized with XRD, BET, TEM/SEM, HR-TEM, H-2-TPR, and XPS to understanding the correlation between the morphology of Co3O4 and the corresponding catalytic performance. Specifically, the straw-like nanorods, flower-like nanosheets, and honeycomb-like nanoparticles of Co3O4 could be controlled with the choice precipitants. Our comprehensive analysis indicated that the straw-like Co3O4 nanorods possessed preferential performance for CO catalytic oxidation among these nanostructured Co3O4 to produce CO2. In addition, the results showed good long-term stability for practical application over the straw-like Co3O4 nanorods and showed no significant decay (the activity maintained 97% conversion) within 50 h at 125 degrees C. The novel insights of low-temperature CO oxidation on nanostructured Co3O4 from this work could hold promise for the development of new strategies and design principles for manufacturing highly active and stable catalysts. [GRAPHICS] .