Hydrogen Adsorption/Desorption Isotherms on Supported Platinum Nanoparticles Determined by in‐situ XAS and ΔXANES Analysis
Hydrogen Adsorption/Desorption Isotherms on Supported Platinum Nanoparticles Determined by in‐situ XAS and ΔXANES Analysis
复制标题
通过原位 XAS 和 ΔXANES 分析确定负载型铂纳米颗粒上的氢吸附/解吸等温线
DOI：
10.1002/cctc.202101709
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发表时间：
2022
期刊：
影响因子：
4.5
通讯作者：
Yoshida Hisao
中科院分区：
文献类型：
--
作者：
Fujita Masami;Yamamoto Akira;Tsuchiya Naoki;Yoshida Hisao
负载金属纳米颗粒（NP）上的氢原子在多相催化中发挥着重要作用。然而，尽管之前进行了大量的研究，氢在实际负载型纳米粒子催化剂上的吸附仍然不清楚，特别是在大气压条件下。本研究通过分析 303 K 下 PtLIII 边缘 X 射线吸收光谱 (XAS) 的差异光谱，在气流条件下获得了氧化铝 (Al2O3) 负载的 Pt NP 上氢的吸附/解吸等温线。通过扩展 X 射线吸收精细结构 (EXAFS) 的分析，观察到氢覆盖率与 Pt−Pt 键距之间存在正线性关系。此外，第一次吸附/解吸循环后的氢重吸附实验以及氢吸附过程中色散 XAS 光谱的瞬态变化表明，在室温和大气压附近，氢吸附诱导了 Al2O3 上 Pt NP 的表面重构。
Hydrogen atoms on supported metal nanoparticles (NPs) play a significant role in heterogeneous catalysis. Despite the extensive previous research, however, the adsorption of hydrogen onto practical supported NP catalysts is still unclear especially in the atmospheric pressure conditions. In this study, adsorption/desorption isotherms of hydrogen on Pt NPs supported on alumina (Al2O3) were obtained in gas‐flow conditions using the analysis of the difference spectra of PtLIII‐edge X‐ray absorption spectroscopy (XAS) at 303 K. From the analysis of extended X‐ray absorption fine structure (EXAFS), a positive linear relationship was observed between the hydrogen coverage and Pt−Pt bond distance. Additionally, the re‐adsorption experiment of hydrogen after the first adsorption/desorption cycle and the transient change of dispersive XAS spectra in the hydrogen adsorption suggests that the hydrogen adsorption induces the surface reconstruction of Pt NPs on Al2O3at around room temperature and atmospheric pressure.
影响因子：
2.5
作者：
Ravel, B;Newville, M
通讯作者：
Newville, M