CO Gas Induced Phase Separation in PtPb@Pt Catalyst and Formation of Ultrathin Pb Nanosheets Probed by In Situ Transmission Electron Microscopy

Wang, Qi1,2; Zhao, Zhi Liang1,2; Gu, Meng1,2

2019-08-22

10.1002/smll.201903122

Small   影响因子和分区

1613-6810

1613-6829

PtPb@Pt catalysts are very useful and widely applied in various industrial reactions. Here, the phase stability of such catalysts is compared in both CO gas and vacuum conditions at elevated temperatures using aberration-corrected in situ transmission electron microscopy (TEM). A Pt aggregation process takes place affected by CO gas, which results in direct exposure of the PtPb core to CO. A phase separation process, in which Pb atoms are stripped off the original PtPb@Pt nanoparticles, is unambiguously identified in CO gas. At initial stages, the as nucleated Pb islands are amorphous. Once the ultrathin Pb islands reach approximate to 3.5 nm or higher, they suddenly became crystalline. The interaction between Pb and CO gas stabilizes the ultrathin Pb nanosheets, resulting in the formation of a large quantity of Pb nanosheets and Pb-depleted PtPb0.08 nanoparticles. In sharp contrast, when heated up in a vacuum, the PtPb@Pt catalyst remains intact. The results of this study shine light on the "toxic" effect of CO that results in failures of many Pt-based catalysts and discloses formation mechanism of ultrathin Pb nanosheets.

CO poisoning core-shell in situ TEM phase separation PtPb

SCI ; EI

英语

第一 ; 通讯

Guangdong Provincial Key Laboratory of Energy Materials for Electric Power[2018B030322001]

Chemistry ; Science & Technology - Other Topics ; Materials Science ; Physics

Chemistry, Multidisciplinary ; Chemistry, Physical ; Nanoscience & Nanotechnology ; Materials Science, Multidisciplinary ; Physics, Applied ; Physics, Condensed Matter

WOS:000483202800001

WILEY-V C H VERLAG GMBH

20193407353589

Binary alloys ; Catalyst supports ; Gases ; High resolution transmission electron microscopy ; In situ processing ; Nanoparticles ; Nanosheets

Thermodynamics:641.1 ; Optical Devices and Systems:741.3 ; Nanotechnology:761 ; Chemical Agents and Basic Industrial Chemicals:803 ; Chemical Products Generally:804 ; Solid State Physics:933

Web of Science

1.Southern Univ Sci & Technol, Dept Mat Sci & Engn, 1088 Xueyuan Blvd, Shenzhen 518055, Guangdong, Peoples R China
2.Shenzhen Engn Res Ctr Novel Elect Informat Mat &, 1088 Xueyuan Blvd, Shenzhen 518055, Guangdong, Peoples R China

Wang, Qi,Zhao, Zhi Liang,Gu, Meng. CO Gas Induced Phase Separation in PtPb@Pt Catalyst and Formation of Ultrathin Pb Nanosheets Probed by In Situ Transmission Electron Microscopy[J]. Small,2019,15(42).

Wang, Qi,Zhao, Zhi Liang,&Gu, Meng.(2019).CO Gas Induced Phase Separation in PtPb@Pt Catalyst and Formation of Ultrathin Pb Nanosheets Probed by In Situ Transmission Electron Microscopy.Small,15(42).

Wang, Qi,et al."CO Gas Induced Phase Separation in PtPb@Pt Catalyst and Formation of Ultrathin Pb Nanosheets Probed by In Situ Transmission Electron Microscopy".Small 15.42(2019).