Anisotropy of Pt nanoparticles on carbon- and oxide-support and their structural response to electrochemical oxidation probed by in situ techniques.

摘要: Identifying the structural response of nanoparticle–support ensembles to reaction conditions is essential determine their structure in catalytically active state as well unravel possible degradation pathways. In this work, we investigate (electronic) carbon- and oxide-supported Pt nanoparticles during electrochemical oxidation by situ X-ray diffraction, absorption spectroscopy dissolution rate mass spectrometry. We prepared ellipsoidal impregnation carbon titanium-based oxide support spherical on an indium-based a surfactant-assisted synthesis route. During oxidation, show that resist (bulk) formation dissolution. The lattice smaller exhibits size-induced contraction as-prepared with respect bulk but it expands reversibly oxidation. This expansion suppressed for bulk-like relaxed lattice. could correlate d-band vacancies metallic expansion. PtOx strongest platelet-like explain higher fraction exposed Pt(100) facets. Of all investigated ensembles, RuO2/TiO2-supported most promising morphological integrity under conditions.