Synthesis and characterization of new promoters based on CeO2-ZrO2-Bi2O3 for automotive exhaust catalysts
Synthesis and characterization of new promoters based on CeO2-ZrO2-Bi2O3 for automotive exhaust catalysts
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DOI：
10.1016/j.cattod.2006.05.015
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发表时间：
2006-09-30
期刊：
影响因子：
5.3
通讯作者：
Imanaka, Nobuhito
中科院分区：
文献类型：
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作者：
Masui, Toshiyuki;Minami, Keisuke;Imanaka, Nobuhito
合成了基于CeO2-ZrO2-Bi2O3固溶体的新型氧化催化剂，用于有效氧化汽车尾气中的烟尘颗粒。通过程序升温还原和O-2脉冲实验研究了CeO2-ZrO2-Bi2O3催化剂的氧化还原行为。CeO2-ZrO2- bi2o3固溶体在300℃以下的氧释放量和1000 μ mol O-2 g（-1）以上的氧存储容量均高于常规CeO2-ZrO2固溶体的594℃和482 μ mol O-2 g（-1）。此外，银的加入促进了CeO2-ZrO2-Bi2O3固溶体的低温还原行为，银是一种透氧组分。该行为的机理是银的部分溶入CeO2-ZrO2-Bi2O3晶格和银在固溶体上的表面沉积的协同作用。催化剂本体中氧的反应性大大提高了烟灰在低温下的燃烧活性。(C) 2006 Elsevier B.V.版权所有
New oxidation catalysts based on CeO2-ZrO2-Bi2O3 solid solutions were synthesized for the effective oxidation of the soot particulates in the automotive emissions. Temperature programmed reduction and O-2 pulses experiments have been performed to examine the redox behavior of the CeO2-ZrO2-Bi2O3 catalysts. The CeO2-ZrO2-Bi2O3 solid solution showed both oxygen release below 300 degrees C and high oxygen storage capacity (OSC) over 1000 mu mol O-2 g(-1), while those of the conventional CeO2-ZrO2 were 594 degrees C and 482 mu mol O-2 g(-1), respectively. Furthermore, the low temperature reduction behavior of the CeO2-ZrO2-Bi2O3 solid solution was promoted by the addition of silver, which is an oxygen permeable component. The mechanism of the behavior was attributed to the synergetic effects of the partial solution of silver into the CeO2-ZrO2-Bi2O3 lattice and the surface deposition of silver on the solid solution. The reactivity of oxygen in the bulk of the catalyst greatly improves the soot combustion activities at low temperatures. (C) 2006 Elsevier B.V. All rights reserved.