Visualization of Gas Distribution in a Model AP-XPS Reactor by PLIF: CO Oxidation over a Pd(100) Catalyst

Catalysts

Jianfeng Zhou¹  Johan Zetterberg¹  Johan Gustafson²  Sara Blomberg²  Edvin Lundgren² 

[1] Division of Combustion Physics, Lund University, SE-221 00 Lund, Sweden;Division of Synchrotron Radiation Research, Lund University, SE-221 00 Lund, Sweden;

关键词: AP-XPS;    PLIF;    boundary layer;    CO oxidation;   

DOI  :  10.3390/catal7010029

来源: DOAJ

【 摘 要 】

In situ knowledge of the gas phase around a catalyst is essential to make an accurate correlation between the catalytic activity and surface structure in operando studies. Although ambient pressure X-ray photoelectron spectroscopy (AP-XPS) can provide information on the gas phase as well as the surface structure of a working catalyst, the gas phase detected has not been spatially resolved to date, thus possibly making it ambiguous to interpret the AP-XPS spectra. In this work, planar laser-induced fluorescence (PLIF) is used to visualize the CO2 distribution in a model AP-XPS reactor, during CO oxidation over a Pd(100) catalyst. The results show that the gas composition in the vicinity of the sample measured by PLIF is significantly different from that measured by a conventional mass spectrometer connected to a nozzle positioned just above the sample. In addition, the gas distribution above the catalytic sample has a strong dependence on the gas flow and total chamber pressure. The technique presented has the potential to increase our knowledge of the gas phase in AP-XPS, as well as to optimize the design and operating conditions of in situ AP-XPS reactors for catalysis studies.

【 授权许可】

Unknown