Nb-containing hematites Fe2-xNbxO3: The role of Nb5 on the reactivity in presence of the H2O2 or ultraviolet light

作者：Silva Adilson C; Oliveira Diana Q L; Oliveira Luiz C A^*; Anastacio Alexandre S; Ramalho Teodorico C; Lopes Joao H; Carvalho Hudson W P; Torres Claudia E Rodriguez

来源：Applied Catalysis A: General , 2009, 357(1): 79-84.

DOI：10.1016/j.apcata.2009.01.014

• Hematite
• Niobium
• Organic oxidation
• ESI-MS

A series of Nb-containing hematites, Fe-2-xNbxO3 (%Nb = 0.00, 1.49, 5.00 and 9.24) was prepared using the conventional co-precipitation method. Mossbauer and temperature-programmed reduction (TPR) measurements suggested the formation of the crystalline phase with partial substitution of Fe3+ by Nb5+ in the structure. N-2 adsorption/desorption revealed that the presence of Nb has a remarkable effect on the textural properties of the material with an increase in the BET surface area. The reactivity of Fe2-xNbxO3 was investigated using the oxidation of the methylene blue dye used as a model pollutant. The obtained results showed that the presence of Nb seems not to act directly promoting the H2O2 decomposition, but improving the dye oxidation. The analysis using the ESI-MS technique showed partial oxidation observed through different intermediates before the mineralization. This suggests the use of Nb-doped hematite as an efficient catalyst in degradation reactions in the presence of H2O2 or ultraviolet light.

• 出版日期2009-3-31