2D-Co3O4 and 3D-Co3O4 catalysts were prepared by the hard template method, and nano-Co3O4 was synthesized by precipitation method. The catalytic activity for the oxidation of formaldehyde over various types of catalysts was investigated. The 3D-Co3O4 catalyst attained a 100% conversion rate of formaldehyde at 130 degrees C with a space velocity of 30,000 mL/(gh), while the 2D-Co3O4 catalyst oxidized formaldehyde completely at 150 degrees C in the same space velocity conditions. The difference in activity is due to the clear channel structure of the mesoporous Co3O4 prepared by the hard template method, which has large specific surface area and surface active species that allows the reactant to diffuse and undergo surface reactions. The 3D-Co3O4 had the best performance of formaldehyde oxidation due to the three-dimensional porous channel structure, larger specific surface area, abundant active surface oxygen species and active Co3+ cationic species on the exposed (2 2 0) crystal face. Complete conversion of formaldehyde had remained the same after 3D-Co3O4 was observed for 160 h. Therefore, the 3D-Co3O4 catalyst has the best catalytic activity and stability for formaldehyde, which might be a non-noble catalyst for catalytic removal of formaldehyde in practical application. (c) 2013 Elsevier B.V. All rights reserved.