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キーワード:
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要旨:
This study presents a systematic detailed experimental and theoretical investigation of the electronic properties of size-controlled free and γ-Al2O3-supported Pt nanoparticles (NPs) and their evolution with decreasing NP size and adsorbate (H2) coverage. A combination of in situX-ray absorption near-edge structure (XANES) and density functional theory (DFT) calculations revealed changes in the electronic characteristics of the NPs due to size, shape, NP–adsorbate (H2) and NP–support interactions. A correlation between the NP size, number of surface atoms and coordination of such atoms, and the maximum hydrogen coverage stabilized at a given temperature is established, with H/Pt ratios exceeding the 1:1 ratio previously reported for bulk Pt surfaces.