The effect of CoOx addition on the performance and structure of V2O5/ZrO2-CeO2 catalyst for simultaneous removal of NO and Hg-0 in simulated flue gas was investigated by various methods including SEM, BET, XRD, XPS, H-2-TPR and FT-IR. It was found that the introduction of CoOx not only greatly enhanced the redox properties of catalysts, but also increased the catalytic performance for simultaneous removal of NO and Hg-0. The CoOx-modified V2O5/ZrO2-CeO2 catalyst displayed excellent catalytic activity for NO conversion (89.6%) and Hg-0 oxidation (88.9%) at 250 degrees C under SCR atmosphere. The synergistic effect among vanadium, cobalt, and the ZrCe support could induce oxygen vacancies formation and promote oxygen mobility via charge transfer. Besides, CoOx could assist vanadium species in rapidly changing the valence by the redox cycle of V5+ + Co2+ <-> V4+ + Co3+. All the above features contribute to the excellent catalytic performance through CoOx addition. (C) 2017 Elsevier B.V. All rights reserved.