Synthesis of mesoporous PrxZr1-xO2-δ solid solution with high thermal stability for catalytic soot oxidation

The fabrication of mesoporous PrxZr1-xO2-delta solid solutions with different Pr/Zr molar ratios is reported in the present work. Based on a systematic investigation, the anion of Zr precursor and template species are found to play the most important roles for the formation of mesoporous structure. The triblock copolymer Pluronic F127 template helps to generate porosity in the matrix by self-assembly into micelle, while the additional Cl-1 from Zr precursor can lead to the enhancement of the interaction between non-ionic micelles. The physicochemical properties of the obtained samples were studied by means of N-2 sorption analysis, TEM, XRD, H-2-TPR, O-2-TPD and XPS technique. It is found that, compared with the non-mesoporous counterparts, the mesoporous PrxZr1-xO2-delta solid solutions possess much higher specific surface area (139 m(2)g(-1)) and enhanced redox ability. Also, the ability to release oxygen is improved after aging at high temperature. For the catalytic soot oxidation, the fresh mesoporous Pr0.1Zr0.9O2-delta catalyst (calcinated at 500 degrees C) shows high activity in a loose contact condition (T-50 = 399 degrees C). It should be highlighted that the T-50 values over the three mesoporous PrxZr1-xO2-delta samples decrease by 8 similar to 24 degrees C after aging at 800 degrees C for 3 h. This suggests that the mesoporous PrxZr1-xO2-delta solid solution is an ideal candidate for catalytic application at high temperatures. (C) 2017 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.