Preparation and catalytic performance of Fe-SBA-15 and FeO x /SBA-15 for toluene combustion

High-surface-area and well-ordered mesoporous Fe-incorporated SBA-15 (xFe-SBA-15) and SBA-15-supported FeO _x (yFeO _x /SBA-15) with the Fe surface density between 0.09 to 1.11 Fe-atom/nm² have been prepared using the one-step synthesis and incipient wetness impregnation methods, respectively. Physicochemical properties of these materials were characterized by means of numerous techniques, and their catalytic activities for the combustion of toluene were evaluated. It is found that the xFe-SBA-15 and yFeO _x /SBA-15 samples possessed rod- or chain-like morphologies. The Fe species were of high dispersion when the Fe surface density was lower than 0.76 Fe-atom/nm² in xFe-SBA-15 and 0.64 Fe-atom/nm² in yFeO _x /SBA-15. At a similar Fe surface density and space velocity, the xFe-SBA-15 catalysts showed better activity than the yFeO _x /SBA-15 catalysts, in which the xFe-SBA-15 catalyst with Fe surface density 0.59 Fe-atom/nm² performed the best. It is concluded that the good performance of the xFe-SBA-15 sample with Fe surface density 0.59 Fe-atom/nm² was associated with its large surface area, high Fe species dispersion, and good low-temperature reducibility.