Metal-organic framework as a host for synthesis of nanoscale Co3O4 as an active catalyst for CO oxidation

Co3O4 nanoparticles were prepared from cobalt nitrate that was accommodated in the pores of a metal-organic framework (MOF) ZIF-8 (Zn(MeIM)(2), MeIM=2-methylimidazole) by using a simple liquid-phase method. The ZIF-8 host was removed by pyrolysis under air and subsequently washing with an NH4Cl-NH3 center dot H2O aqueous solution. Transmission electron microscopy (TEM) analysis shows that the obtained Co3O4 is composed of separate nanoparticles with a mean size of 18 nm. The Co3O4 nanoparticles exhibit excellent catalytic activity, cycling stability, and long-term stability in the low temperature CO oxidation. (C) 2011 Elsevier B.V. All rights reserved.