Busca avançada
Ano de início
Entree
(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

Impact of Transition Metal Carbide and Nitride Supports on the Electronic Structure of Thin Platinum Overlayers

Texto completo
Autor(es):
Garg, Aaron [1] ; Goncalves, Danielle S. [2] ; Liu, Yusu [3] ; Wang, Zhenshu [1] ; Wang, Linxi [4] ; Yoo, Jong Suk [5] ; Kolpak, Alexie [5] ; Rioux, Robert M. [6, 4] ; Zanchet, Daniela [2] ; Roman-Leshkov, Yuriy [1]
Número total de Autores: 10
Afiliação do(s) autor(es):
[1] MIT, Dept Chem Engn, Cambridge, MA 02139 - USA
[2] Univ Estadual Campinas, Inst Chem, BR-13083970 Campinas, SP - Brazil
[3] MIT, Dept Mat Sci & Engn, Cambridge, MA 02139 - USA
[4] Penn State Univ, Dept Chem Engn, University Pk, PA 16802 - USA
[5] MIT, Dept Mech Engn, Cambridge, MA 02139 - USA
[6] Penn State Univ, Dept Chem, University Pk, PA 16802 - USA
Número total de Afiliações: 6
Tipo de documento: Artigo Científico
Fonte: ACS CATALYSIS; v. 9, n. 8, p. 7090-7098, AUG 2019.
Citações Web of Science: 0
Resumo

Atomically thin platinum (Pt) shells on titanium tungsten carbide (TiWC) and titanium tungsten nitride (TiWN) core nanoparticles display substantially modified catalytic performance compared to commercial Pt nanoparticles. In situ X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) analyses indicate these differences are primarily caused by ligand effects from the hybridization of Pt and W d states at the core-shell interface. The heterometallic bonding between the shell and the core elements leads to broadening of the Pt valence d-band, a downshift of the d-band center, and greatly reduced adsorbate binding energies, as verified by density functional theory calculations and microcalorimetry of CO adsorption. In situ XANES measurements during reduction treatment demonstrated how surface oxides disrupt the bonding interactions between Pt and W. Changes to the Pt electronic structure from different core materials correlated with ethylene hydrogenation reactivity, where increased Pt d-band broadening was associated with weaker adsorbate binding and consequently lower turnover frequency. The significant electronic structure modification of Pt by the TiWC and TiWN cores exemplifies how core-shell nanoparticle architectures can be used to tune catalyst reactivity. (AU)

Processo FAPESP: 15/50375-6 - Engineering co-resistant catalysts for hydrogen gas clean-up
Beneficiário:Daniela Zanchet
Linha de fomento: Auxílio à Pesquisa - Regular
Processo FAPESP: 15/23900-2 - Avaliação de materiais alternativos abundantes como próxima geração de catalisadores para conversão de biomassa lignocelulósica
Beneficiário:Daniela Zanchet
Linha de fomento: Bolsas no Exterior - Pesquisa