High-surface-area and well-ordered mesoporous Fe-incorporated SBA-15(xFe-SBA-15)and SBA-15-supported FeOx(yFeOx/SBA-15)with the Fe surface density between 0.09 to 1.11 Fe-atom/nm2have 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 yFeOx/SBA-15 samples possessed rod-or chain-like morphologies.The Fe species were of high dispersion when the Fe surface density was lower than0.76 Fe-atom/nm2in xFe-SBA-15 and 0.64 Fe-atom/nm2in yFeOx/SBA-15.At a similar Fe surface density and space velocity,the xFe-SBA-15 catalysts showed better activity than the yFeOx/SBA-15 catalysts,in which the xFe-SBA-15 catalyst with Fe surface density 0.59 Fe-atom/nm2performed the best.It is concluded that the good performance of the xFe-SBA-15 sample with Fe surface density0.59 Fe-atom/nm2was associated with its large surface area,high Fe species dispersion,and good low-temperature reducibility.
