Direct sulfation of Zr-Co hydroxides provides a significant advantage over traditional impregnation by conserving Bronsted acid sites for the introduction of a second active component and also for subsequent catalytic reactions. After Pd loading, sulfated Zr-Co exhibits excellent activity, selectivity, and durability for the selective catalytic reduction of NOx by methane. Using Co K-edge X-ray absorption spectroscopy, we provide the direct evidence of the entrance of Co into the lattice of cubic zirconia to form a substitutional solid solution. (C) 2011 Elsevier Inc. All rights reserved.