The mixed oxides, VCe and VCe0.95M0.05 (M=Cu, Co, Mn, Fe and Cr), we re prepared by sol-gel method. The structure and redox properties of these mixe d oxides were characterized by XRD, Raman, XPS and TPR techniques. The main phas e is tetragonal VCeO4 phase in all samples. The substitution of Fe, Mn, Cu or Co for Ce results in the formation of CeO2 or monoclinic VCeO4 phase. The XP S result indicates that valence of V is +5+δ(δ<1) in VCe0.95Co0 .05, VCe0.95Mn0.05, VCe0.95Cr0.05 and VCe0.95Fe 0.05 samples compared with VCe , on the contrary, valence of V is +5-δ (δ<1) in VCe0.95Cu0.05 sample. The Fe, Co, Cr and Mn enhanc e the reduction of V5+ in VCeO4, whereas Cu inhibits this reduction.
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