Perovskite-type oxides have been widely applied in heterogeneous catalytic reactions, such as soot oxidation. However, a poor contact point between the catalyst and solid reactant (soot) often limits the catalytic performance. Here, we report La1 - xSrxCo0.2Fe0.8O3 - δ perovskite oxide catalysts with a unique three-dimensional (3D) fiber web structure that increases the high-contact area by trapping soot in the unique pore structure for effective catalytic activity. This feature was carefully analyzed using scanning transmission electron microscopy (STEM) tomography to investigate the location of the soot on the web. The structure of the web, with a thickness of approximately 55 μm, indicated that the soot particles were caught by the 3D pores between the fibers. The relationship between the Sr amount and activate oxygen was also characterized by means of XPS. The results show that the Sr amount of 0.4 produced the highest amount of active oxygen species (O-) that are essential for soot oxidation reaction. The developed catalyst exhibited a good catalytic performance due to the optimized perovskite chemical structure and the greatly increased number of the contact points owing to the 3D inter-fiber spaces. Hence, our proposed approach is reasonable for application to real soot combustion processes and can also be easily extended to numerous other catalytic processes to enhance the catalytic activity.
Bibliographical noteFunding Information:
This article is dedicated to the memory of the late Professor Y. Teraoka, who passed away unexpectedly on July 2, 2014. We would like to express our sincere respect and gratitude to his exceptional contributions towards the study of catalysis and perovskites. Industrial Technology Innovation Program funded by the Ministry Of Trade, Industry and Energy (MOTIE), Republic of Korea (grant number 10052076).
© 2016 Elsevier B.V.
All Science Journal Classification (ASJC) codes
- Environmental Science(all)
- Process Chemistry and Technology