Nuclear Techniques ›› 2018, Vol. 41 ›› Issue (12): 120501-120501.doi: 10.11889/j.0253-3219.2018.hjs.41.120501

• NUCLEAR PHYSICS, INTERDISCIPLINARY RESEARCH • Previous Articles     Next Articles

In-situ studies of CO oxidation on Pt(110)

LI Chang1,2,3, CAI Jun1,2, YANG Tian1,3, HAN Yong1,2, DONG Qiao1,3, LI Yimin1,2, LIU Zhi1,2   

  1. 1 State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050, China;
    2 School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China;
    3 University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2018-09-04 Revised:2018-10-11 Online:2018-12-10 Published:2018-12-13
  • Supported by:
    Supported by National Natural Science Foundation of China (No.11227902), Science and Technology Commission of Shanghai Municipality (No.14520722100)

Abstract: [Background] CO oxidation is a very important prototypical reaction in heterogeneous process. The reaction mechanism of Pt-group metals under ultrahigh vacuum (UHV) conditions was studied in detail, and unambiguous evidence of Langmuir-Hinshelwood kinetics was found. However, the reaction mechanism of the Pt(110) surface under high pressure conditions was still controversial.[Purpose] This study aims to clarify the reaction mechanism and active sites of CO oxidation on Pt(110).[Methods] The oxidation of CO on Pt(110) surface was studied under total pressures up to 100 Pa in different CO:O2 reaction mixtures. Surface species and composition of products were analyzed in situ by ambient pressure X-ray photoelectron spectroscopy (APXPS) and online gas analysis by mass spectra (MS).[Results] The process of CO oxidation on Pt(110) fell into three regimes:1) low active regime with CO poisoned Pt(110) surface and low CO2 formation rate; 2) highly active regime with ignition reaction on Pt(110) surface companied by a large amount of heat release; 3) mass transfer rate limited regime, excessive O-rich Pt(110) surface, the CO2 formation rate controlled by CO diffusion rate.[Conclusion] The active sites of CO oxidation reaction on Pt(110) surface are metallic Pt.

Key words: CO oxidation, Pt(110) surface, Catalysis, APXPS, Mass spectra

CLC Number: 

  • O647