Co3O4 nanoflower clusters were fabricated by a simple low-temperature hydrothermal method. The properties of Co3O4 nanomaterials were comprehensively determined by combining different analytical techniques. The self-assembled Co3O4 nanoflower clusters had good crystallinity and porous structure. They were utilized as the catalyst for the degradation of gaseous toluene. The experimental results showed that the catalytic activity of the as-prepared Co3O4 nanoflower clusters was much superior to the Co3O4 blocks under the same reaction conditions. (C) 2012 Elsevier B.V. All rights reserved.