Factors influencing hydride formation in a Pd/TiO2 catalyst.
Factors influencing hydride formation in a Pd/TiO2 catalyst.
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DOI：
10.1021/jp062205l
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发表时间：
2006-08
期刊：
影响因子：
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通讯作者：
Jacinto Sá;G. Arteaga;R. Daley;J. Bernardi;J. Anderson
中科院分区：
文献类型：
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作者：
Jacinto Sá;G. Arteaga;R. Daley;J. Bernardi;J. Anderson
对一个含有沉积在二氧化钛（TiO₂）上的钯纳米粒子的样品进行了一系列不同的热预处理。选择这些处理的范围是为了使钯表面处于多种不同状态，包括形成了TiOₓ覆盖层的形式。进行实验以确定钯表面的状态如何影响钯氢化物的形成。在程序升温实验过程中释放的氢气量被用于量化在室温下暴露于氢气后钯β - 氢化物形成的程度。通过具有能谱分析（EDX）的高角度环形暗场（HAADF）电子显微镜、一氧化碳脉冲化学吸附以及吸附一氧化碳的傅里叶变换红外光谱（FTIR）对样品进行了表征。发现钯β - 氢化物形成的量和难易程度取决于金属表面积、二氧化钛覆盖层的存在以及钯表面粗糙度/缺陷浓度。
A sample containing Pd nanoparticles deposited on TiO(2) was subjected to a series of different thermal pretreatments. The range of these treatments was selected to provide a palladium surface in a number of different states, including a form where TiO(x) overlayers had been formed. Experiments were conducted to determine how the state of the Pd surface influenced the formation of Pd hydride. The amount of hydrogen released during a temperature-programmed experiment was used to quantify the extent of Pd beta-hydride formation following room-temperature exposure to hydrogen. Samples were characterized by HAADF (high-angle annular dark-field) electron microscopy with EDX (energy-dispersive X-ray) analysis and CO pulse chemisorption and FTIR (Fourier transform infrared spectroscopy) of adsorbed CO. The amount and the ease with which Pd beta-hydride was formed was found to be dependent on the metal surface area, the presence of titania overlayers, and the Pd surface roughness/defect concentration.