New insights into the role of Pd-Ce interface for methane activation on monolithic supported Pd catalysts: A step forward the development of novel PGM Three-Way Catalysts for natural gas fueled engines
New insights into the role of Pd-Ce interface for methane activation on monolithic supported Pd catalysts: A step forward the development of novel PGM Three-Way Catalysts for natural gas fueled engines
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关于 Pd-Ce 界面在整体负载 Pd 催化剂上甲烷活化作用的新见解：天然气燃料发动机新型 PGM 三元催化剂的开发向前迈出了一步
DOI：
10.1016/j.apcatb.2019.118475
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发表时间：
2020-05-05
影响因子：
22.1
通讯作者：
Chen, Yaoqiang
中科院分区：
文献类型：
--
作者：
Chen, Jianjun;Wu, Yang;Chen, Yaoqiang
研究了焙烧温度对Pd/Al 2 O3-CeO 2三效催化剂处理天然气汽车尾气性能的影响。从550 ° C至950 ° C的煅烧产生在1.9- 8.5nm范围内的Pd颗粒。发现在化学计量NGV条件下，PdO可以被还原成更活性的Pd-O物质。更具体地说，1.9 nm的Pd颗粒，发展更强的Pd-Ce相互作用被发现更可还原，并对应于增强的催化性能，对甲烷减排。在较高的煅烧温度下，对应于较大的Pd颗粒，Pd-Ce界面的劣化伴随着较低的TOF和较高的活化势垒。因此，Pd-0-PdO相互作用变得普遍以活化甲烷。基于这些观察，得出结论，与Pd颗粒尺寸相关的Pd-0-Ce和Pd-0-PdO界面可以被认为是用于鉴定Pd基NGV催化剂的性能的标准。
This study reports a significant impact of the calcination temperature on the performances of Pd/Al2O3-CeO2 Three-Way-Catalysts to treat exhaust from natural gas fueled vehicles. Calcination from 550 degrees C to 950 degrees C led to Pd particles in the range 1.9-8.5 nm. It was found that PdO can be reduced to more active Pd-0 species under stoichiometric NGV conditions. More specifically, the 1.9 nm Pd particles, developing stronger Pd-Ce interaction were found more reducible and correspond to enhanced catalytic properties towards methane abatement. At high calcination temperature, corresponding to larger Pd particles, the deterioration of the Pd-Ce interface is accompanied with lower TOF jointly with higher activation barriers. Accordingly, the Pd-0-PdO interaction becomes prevalent to activate methane. Based on these observations, it was concluded that Pd-0-Ce and Pd-0-PdO interface related to the Pd particle size may be considered as criteria for identifying the performance of Pd-based NGV catalysts.