In situ determination of the nanostructure effects on the activity, stability and selectivity of Pt-Sn ethanol oxidation catalysts
Nanoparticle catalysts comprising two PtSn alloys with different Pt:Sn atomic ratios and a Sn modified Pt catalyst were prepared in order to study the effect of the particle nanostructures on the activity towards the ethanol electrooxidation and the selectivity to CO2. An accurate model of the elect...
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2018
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| Acceso en línea: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_15726657_v819_n_p136_Calvillo http://hdl.handle.net/20.500.12110/paper_15726657_v819_n_p136_Calvillo |
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paper:paper_15726657_v819_n_p136_Calvillo2023-06-08T16:24:49Z In situ determination of the nanostructure effects on the activity, stability and selectivity of Pt-Sn ethanol oxidation catalysts Ethanol electrooxidation In situ FTIRS In situ XAFS Pt-Sn nanostructures Structural stability Binary alloys Carbon dioxide Catalyst activity Catalyst selectivity Catalysts Electronic structure Electrooxidation Ethanol Fourier transform infrared spectroscopy Nanostructures Oxidation Platinum Reaction intermediates Stability Thallium alloys Tin Tin alloys Tin compounds X ray absorption spectroscopy Electronic and structural properties Electronic environments Ethanol electro-oxidation In-situ X-ray absorption spectroscopy Nanoparticle catalysts Situ XAFS Sn nanostructures Structural stabilities Platinum alloys Nanoparticle catalysts comprising two PtSn alloys with different Pt:Sn atomic ratios and a Sn modified Pt catalyst were prepared in order to study the effect of the particle nanostructures on the activity towards the ethanol electrooxidation and the selectivity to CO2. An accurate model of the electronic and structural properties, obtained by ex situ analysis, was established. Alloying of Sn with Pt causes the expansion of the lattice parameter of Pt and modifies its electronic structure. In contrast, the deposition of Sn on the Pt surface has neither effect. The activity of the catalysts towards ethanol oxidation was established voltammetrically and the CO2 selectivity via in situ Fourier transform infrared spectroscopy (FTIRS). Results indicated that the modification of the electronic environment of Pt in Pt-Sn alloys results in a weaker adsorption of the intermediates (acetaldehyde and acetic acid), which desorb easily from the surface of the catalyst resulting in incomplete oxidation to CO2. In contrast, when the electronic structure is not perturbed (Sn modified Pt sample), the amount of CO2 produced increases. The stability of the different nanostructures under working conditions was investigated by in situ X-ray absorption spectroscopy (XAS) measurements, which show that initially both the Sn modified Pt and Pt-Sn alloy nanostructures are stable under applied potential in the potential window studied and in presence of ethanol. Accelerated aging studies showed that the Sn modified Pt nanostructure remained stable, whereas a significant structural change was observed for the Pt-Sn alloys. © 2017 Elsevier B.V. 2018 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_15726657_v819_n_p136_Calvillo http://hdl.handle.net/20.500.12110/paper_15726657_v819_n_p136_Calvillo |
| institution |
Universidad de Buenos Aires |
| institution_str |
I-28 |
| repository_str |
R-134 |
| collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
| topic |
Ethanol electrooxidation In situ FTIRS In situ XAFS Pt-Sn nanostructures Structural stability Binary alloys Carbon dioxide Catalyst activity Catalyst selectivity Catalysts Electronic structure Electrooxidation Ethanol Fourier transform infrared spectroscopy Nanostructures Oxidation Platinum Reaction intermediates Stability Thallium alloys Tin Tin alloys Tin compounds X ray absorption spectroscopy Electronic and structural properties Electronic environments Ethanol electro-oxidation In-situ X-ray absorption spectroscopy Nanoparticle catalysts Situ XAFS Sn nanostructures Structural stabilities Platinum alloys |
| spellingShingle |
Ethanol electrooxidation In situ FTIRS In situ XAFS Pt-Sn nanostructures Structural stability Binary alloys Carbon dioxide Catalyst activity Catalyst selectivity Catalysts Electronic structure Electrooxidation Ethanol Fourier transform infrared spectroscopy Nanostructures Oxidation Platinum Reaction intermediates Stability Thallium alloys Tin Tin alloys Tin compounds X ray absorption spectroscopy Electronic and structural properties Electronic environments Ethanol electro-oxidation In-situ X-ray absorption spectroscopy Nanoparticle catalysts Situ XAFS Sn nanostructures Structural stabilities Platinum alloys In situ determination of the nanostructure effects on the activity, stability and selectivity of Pt-Sn ethanol oxidation catalysts |
| topic_facet |
Ethanol electrooxidation In situ FTIRS In situ XAFS Pt-Sn nanostructures Structural stability Binary alloys Carbon dioxide Catalyst activity Catalyst selectivity Catalysts Electronic structure Electrooxidation Ethanol Fourier transform infrared spectroscopy Nanostructures Oxidation Platinum Reaction intermediates Stability Thallium alloys Tin Tin alloys Tin compounds X ray absorption spectroscopy Electronic and structural properties Electronic environments Ethanol electro-oxidation In-situ X-ray absorption spectroscopy Nanoparticle catalysts Situ XAFS Sn nanostructures Structural stabilities Platinum alloys |
| description |
Nanoparticle catalysts comprising two PtSn alloys with different Pt:Sn atomic ratios and a Sn modified Pt catalyst were prepared in order to study the effect of the particle nanostructures on the activity towards the ethanol electrooxidation and the selectivity to CO2. An accurate model of the electronic and structural properties, obtained by ex situ analysis, was established. Alloying of Sn with Pt causes the expansion of the lattice parameter of Pt and modifies its electronic structure. In contrast, the deposition of Sn on the Pt surface has neither effect. The activity of the catalysts towards ethanol oxidation was established voltammetrically and the CO2 selectivity via in situ Fourier transform infrared spectroscopy (FTIRS). Results indicated that the modification of the electronic environment of Pt in Pt-Sn alloys results in a weaker adsorption of the intermediates (acetaldehyde and acetic acid), which desorb easily from the surface of the catalyst resulting in incomplete oxidation to CO2. In contrast, when the electronic structure is not perturbed (Sn modified Pt sample), the amount of CO2 produced increases. The stability of the different nanostructures under working conditions was investigated by in situ X-ray absorption spectroscopy (XAS) measurements, which show that initially both the Sn modified Pt and Pt-Sn alloy nanostructures are stable under applied potential in the potential window studied and in presence of ethanol. Accelerated aging studies showed that the Sn modified Pt nanostructure remained stable, whereas a significant structural change was observed for the Pt-Sn alloys. © 2017 Elsevier B.V. |
| title |
In situ determination of the nanostructure effects on the activity, stability and selectivity of Pt-Sn ethanol oxidation catalysts |
| title_short |
In situ determination of the nanostructure effects on the activity, stability and selectivity of Pt-Sn ethanol oxidation catalysts |
| title_full |
In situ determination of the nanostructure effects on the activity, stability and selectivity of Pt-Sn ethanol oxidation catalysts |
| title_fullStr |
In situ determination of the nanostructure effects on the activity, stability and selectivity of Pt-Sn ethanol oxidation catalysts |
| title_full_unstemmed |
In situ determination of the nanostructure effects on the activity, stability and selectivity of Pt-Sn ethanol oxidation catalysts |
| title_sort |
in situ determination of the nanostructure effects on the activity, stability and selectivity of pt-sn ethanol oxidation catalysts |
| publishDate |
2018 |
| url |
https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_15726657_v819_n_p136_Calvillo http://hdl.handle.net/20.500.12110/paper_15726657_v819_n_p136_Calvillo |
| _version_ |
1768541674092363776 |