A novel Cu-doped cerium oxide nanofibers catalyst was prepared via electrospinning and used for preferential CO oxidation (CO-PROX). The microstructure of as-prepared catalyst was characterized by XRD, BET, XPS, SEM, HRTEM, and H(2)-TPR. The results derived from catalytic reaction showed that the obtained Cu(0.1)Ce(0.9)O(2-x) nanofiber is an efficient catalyst for CO-PROX and the concentration of CO in tail gas can be reduced below than 100 ppm. The high catalytic activity of Cu(0.1)Ce(0.9)O(2-x) nanofiber is attributed to the high surface areas and the special fiber-like nanostructure with highly dispersed and active Cu(2+) ions. (C) 2010 Elsevier B.V. All rights reserved.