首页> 美国卫生研究院文献>ACS AuthorChoice >CO Adsorption on Reconstructed Ir(100) Surfaces fromUHV to mbar Pressure: A LEED TPD and PM-IRAS Study
【2h】

CO Adsorption on Reconstructed Ir(100) Surfaces fromUHV to mbar Pressure: A LEED TPD and PM-IRAS Study

机译:碳在重构Ir(100)表面上的吸附特高压至毫巴压力:LEEDTPD和PM-IRAS研究

代理获取
本网站仅为用户提供外文OA文献查询和代理获取服务,本网站没有原文。下单后我们将采用程序或人工为您竭诚获取高质量的原文,但由于OA文献来源多样且变更频繁,仍可能出现获取不到、文献不完整或与标题不符等情况,如果获取不到我们将提供退款服务。请知悉。

摘要

Clean and stable surface modifications of an iridium (100) single crystal, i.e., the (1 × 1) phase, the (5 × 1) reconstruction, and the oxygen-terminated (2 × 1)-O surface, were prepared and characterized by low energy electron diffraction (LEED), temperature-programmed desorption (TPD), infrared reflection absorption spectroscopy (IRAS) and polarization modulation IRAS (PM-IRAS). The adsorption of CO in UHV and at elevated (mbar) pressure/temperature was followed both ex situ and in situ on all three surface modifications, with a focus on mbar pressures of CO. The Ir(1 × 1) surface exhibited c(4 × 2)/c(2 × 2) and c(6 × 2) CO structures under low pressure conditions, and remained stable up to 100 mbar and 700 K. For the (2 × 1)-O reconstruction CO adsorption induced a structural change from (2 × 1)-O to (1 × 1), as confirmed by LEED, TPD, and IR. For Ir (2 × 1)-O TPD indicated that CO reacted with surface oxygen forming CO2. The (5 × 1) reconstruction featured a reversible and dynamic behavior upon CO adsorption, witha local lifting of the reconstruction to (1 × 1). After CO desorption,the (5 × 1) structure was restored. All three reconstructionsexhibited CO adsorption with on-top geometry, as evidenced by IR.With increasing CO exposure the resonances shifted to higher wavenumber,due to adsorbate–adsorbate and adsorbate–substrate interactions.The largest wavenumber shift (from 2057 to 2100 cm–1) was observed for Ir(5 × 1) upon CO dosing from 1 L to 100mbar.
机译:制备并表征了铱(100)单晶的清洁且稳定的表面修饰,即(1×1)相,(5×1)重构和氧封端的(2×1)-O表面通过低能电子衍射(LEED),程序升温脱附(TPD),红外反射吸收光谱(IRAS)和偏振调制IRAS(PM-IRAS)。在这三个表面修饰上都进行了非原位和原位CO在特高压中和在(mbar)压力/温度升高下的吸附,重点是CO的毫巴压力。Ir(1×1)表面表现出c(4 ×2)/ c(2×2)和c(6×2)CO结构在低压条件下保持稳定,直至100 mbar和700K。在(2×1)-O重建中,CO吸附诱导了结构由LEED,TPD和IR确认,从(2×1)-O变为(1×1)。对于Ir(2×1)-O,TPD表明CO与表面氧反应形成CO2。 (5×1)重建具有CO吸附时可逆和动态的特性,具有将重建局部提升为(1×1)。一氧化碳解吸后(5×1)结构已恢复。所有三个重建IR证明,其具有顶部几何形状的CO吸附。随着CO暴露量的增加,共振移向更高的波数,由于吸附物-吸附物和吸附物-底物的相互作用。当CO从1 L增加到100时,Ir(5×1)观察到最大波数位移(从2057到2100 cm –1 )毫巴

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
代理获取

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号