CO-induced removal of the Pt{100}-hex reconstruction studied by RAIRS
CO-induced removal of the Pt{100}-hex reconstruction studied by RAIRS
复制标题
RAIRS 研究的 CO 诱导去除 Pt{100}-hex 重建
DOI：
10.1039/ft9969204781
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发表时间：
1996
期刊：
影响因子：
--
通讯作者：
D. King
中科院分区：
文献类型：
--
作者：
Minseok Kim;W. Sim;D. King
反射-吸收红外光谱（RAIRS）已被用来跟踪CO诱导的去除Pt{100}-六角表面重建在387 K和一系列的环境CO压力。在ca.在5 × 10-10 mbar下暴露3 min，在2069 cm-1处开始出现六角形表面上的线性CO带。在2 × 10-9 mbar下，在2080 cm-1处观察到第二个谱带，该谱带被指定为在成核（1 × 1）区域吸附的线性CO。在2 × 10-8 ~ 5 × 10-8 mbar范围内，CO的吸收带强度急剧增加，其频率移动到2086 cm-1，与扩展（1 × 1）表面上的线性CO相一致。LEED观测证实了这种光谱的剧烈变化是由六角重建的提升引起的。以这种方式，在CO覆盖度低至约100 ° C时观察到CO诱导的Pt{100}-hex重构的去除的开始。0.01单层（ML），通过RAIRS。在现有数据的基础上重新分配了Martin、Gardner和Bradshaw最近的室温RAIRS数据。
Reflection–absorption infrared spectroscopy (RAIRS) has been used to follow the CO-induced removal of the Pt{100}-hex surface reconstruction at 387 K and a range of ambient CO pressures. After ca. 3 min exposure at 5 × 10–10 mbar, a band assigned to linear CO on the hex surface starts to appear at 2069 cm–1. At 2 × 10–9 mbar a second band assigned to linear CO adsorbed at nucleating (1 × 1) areas is observed at 2080 cm–1. Between 2 × 10–8 and 5 × 10–8 mbar, the intensity of the CO absorption band increases dramatically and its frequency shifts to 2086 cm–1, consistent with linear CO on the extended (1 × 1) surface. Visual LEED observation confirms that this dramatic change of the spectrum is caused by the lifting of the hex reconstruction. In this way the initiation of the CO-induced removal of the Pt{100}-hex reconstruction is observed at CO coverages as low as ca. 0.01 monolayers (ML) by RAIRS. Recent room-temperature RAIRS data of Martin, Gardner and Bradshaw are reassigned on the basis of the present data.