Time-Resolved Infrared Emission Studies of CO2 Formed by Catalytic Oxidation of CO on Pt and Pd Surfaces
Time-Resolved Infrared Emission Studies of CO2 Formed by Catalytic Oxidation of CO on Pt and Pd Surfaces
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CO 在 Pt 和 Pd 表面催化氧化形成的 CO2 的时间分辨红外发射研究
DOI：
10.1246/bcsj.65.2450
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发表时间：
1992
影响因子：
4
通讯作者：
G. L. Haller
中科院分区：
文献类型：
--
作者：
K. Kunimori;G. L. Haller
用时间分辨FTIR发射光谱检测了CO在铂和钯表面催化氧化生成的振动激发气相CO2。在900K下，向表面提供连续的O2分子束和脉冲CO通量(200μS半高宽)，并用30μS时间分辨率分析了产物的红外发射，研究了内能与表面氧覆盖度的关系。通过分析时间分辨红外光谱(4厘米−1分辨率)的带宽和质心，可以估计二氧化碳分子的转动温度和平均振动温度(Tr和Tv)。在铂表面低CO喷嘴压力下，红外信号强度几乎与流向表面的随时间变化的CO通量平行，而红外光谱变化相对较小。分析表明，Tv和Tr均随表面氧覆盖度的降低而减小，且Tr的变化比Tv的变化更显著。在较高的CO喷嘴压力下，反应速度较快。
Time-resolved FTIR emission spectroscopy was used to detect vibrationally excited gas phase CO2 formed by the catalytic oxidation of CO on Pt and Pd surfaces. A continuous molecular beam of O2 and a pulsed flux of CO (200 μs FWHM) were supplied to the surface at 900 K, and the infrared emission of the CO2 product was analyzed with 30 μs time resolution to study the dependence of the internal energy on surface oxygen coverage. Analysis of the band width and centroid of the time-resolved infrared spectra (4 cm−1 resolution) allows an estimation of the rotational and average vibrational temperatures (TR and TV ) of the CO2 molecules. At a low CO nozzle pressure on a Pt surface, the infrared signal intensity almost parallels the time dependent CO flux to the surface with relatively small changes in the infrared spectra. The analysis showed that both TV and TR decrease with decreasing surface oxygen coverage and that the change in TR is more significant than that in TV. At a high CO nozzle pressure, the reacti...