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Li X, Yang G, Zhang Q, Liu Z, Peng F. Alkali Metal Cation-Sulfate Anion Ion Pairs Promoted the Cleavage of C-C Bond During Ethanol Electrooxidation. J Phys Chem Lett 2023:11177-11182. [PMID: 38055448 DOI: 10.1021/acs.jpclett.3c02569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/08/2023]
Abstract
Direct ethanol fuel cells show great promise as a means of converting biomass ethanol derived from biomass into electricity. However, the efficiency of complete conversion is hindered by the low selectivity in breaking the C-C bond. This selectivity is determined by factors such as the material structure and reaction conditions, including the nature of the supporting electrolyte. Cations serve not only as facilitators of electricity conduction through ion migration but also as influencers of the reaction pathways. In this study, we utilized differential electrochemical mass spectrometry to track the in situ generation of CO2 during potential scanning. The presence of alkali cations led to an enhancement in the CO2 selectivity. In addition, in situ Raman spectroscopy provided evidence of the formation of alkali metal cation-sulfate anion ion pairs. The catalytic activity and CO2 selectivity were found to be directly correlated to the ionic strength of these ion pairs.
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Affiliation(s)
- Xiang Li
- School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, China
| | - Guangxing Yang
- School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, China
| | - Qiao Zhang
- School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, China
| | - Zhiting Liu
- School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, China
| | - Feng Peng
- School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, China
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Liu G, Peng L, Fan L, Wang J, Fu Y, Cao L, Wu W. Trimetallic PtTiMg Alloy Nanoparticles with High Activity for Efficient Electrocatalytic Ethanol Oxidation. CATALYSIS SURVEYS FROM ASIA 2022. [DOI: 10.1007/s10563-022-09355-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Electrochemical Characterization of Low-Temperature Direct Ethanol Fuel Cells using Direct and Alternate Current Methods. Electrocatalysis (N Y) 2019. [DOI: 10.1007/s12678-019-00559-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
AbstractHere, we report for the first time the results of systematic characterization of a low-temperature polymer electrolyte membrane direct ethanol fuel cell using DC and AC electrochemical methods. Model catalysts (carbon supported Pt nanoparticles) painted on carbon paper are used as anode and cathode. Influence of physical parameters, such as cell temperature, current density, and ethanol concentration, and anode fuel flow rate on overall cell impedance is studied. Analysis of the obtained impedance spectra in connection with DC measurements allows us to comment on cell properties and to separate different contributions to the overall cell polarization. Our results suggest that the cell impedance is dominated by anode faradaic impedance, with a small or negligible contribution from cathode faradaic impedance. The anode impedance depends strongly on current density and cell temperature, but is not significantly influenced by ethanol concentration. Presence of anode mass-transfer impedance, even when ethanol was fed to the cell in high excess, is confirmed. Based on the results, we conclude that changes in ethanol electro-oxidation mechanism might manifest themselves on the impedance spectra in the low-frequency inductive loop. Nonetheless, further studies involving equivalent circuit modelling are needed to determine the exact influence of the cell parameters on the anode kinetics.
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Wang X, Fan W, Zhang C, Chi M, Zhu A, Zhang Q, Liu Q. Well-dispersed Pd–Sn nanocatalyst anchored on TiO2 nanosheets with enhanced activity and durability for ethanol electarooxidation. Electrochim Acta 2019. [DOI: 10.1016/j.electacta.2019.134588] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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On the Influence of Composition and Structure of Carbon-Supported Pt-SnO2 Hetero-Clusters onto Their Electrocatalytic Activity and Durability in PEMFC. Catalysts 2019. [DOI: 10.3390/catal9100803] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
A detailed study of the structure, morphology and electrochemical properties of Pt/C and Pt/x-SnO2/C catalysts synthesized using a polyol method has been provided. A series of catalysts supported on the SnO2-modified carbon was synthesized and studied by various methods including transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), electrochemical methods, and fuel cell testing. The SnO2 content varies from 5 to 40 wt %. The TEM images, XRD and XPS analysis suggested the Pt-SnO2 hetero-clusters formation. The SnO2 content of ca. 10% ensures an optimal catalytic layer structure and morphology providing uniform distribution of Pt-SnO2 clusters over the carbon support surface. Pt/10wt %-SnO2/C catalyst demonstrates increased activity and durability toward the oxygen reduction reaction (ORR) in course of accelerated stress testing due to the high stability of SnO2 and its interaction with Pt. The polymer electrolyte membrane fuel cell current–voltage performance of the Pt/10wt %-SnO2/C is comparable with those of Pt/C, however, higher durability is expected.
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Yang G, Farsi L, Mei Y, Xu X, Li A, Deskins NA, Teng X. Conversion of Ethanol via C-C Splitting on Noble Metal Surfaces in Room-Temperature Liquid-Phase. J Am Chem Soc 2019; 141:9444-9447. [PMID: 31150576 DOI: 10.1021/jacs.8b13115] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Rh-catalyzed decomposition of ethanol into CO2 and CH4 via C-C bond splitting is reported in room-temperature liquid phase under atmospheric pressure. Mechanistic investigations show that C-C bond splitting of ethanol on the noble metal surface is rapid, and CO2 forms through the oxidation of α-CH xO and β-CH x fragments after C-C bond splitting, while CH4 forms through the hydrogenation of β-CH x utilizing H atoms from -OH, β-CH x, and α-CH xOH fragments.
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Affiliation(s)
- Guangxing Yang
- Department of Chemical Engineering , University of New Hampshire , Durham , New Hampshire 03824 , United States.,School of Chemistry and Chemical Engineering , South China University of Technology , Guangzhou , Guangdong 510640 , China
| | - Lida Farsi
- Department of Chemical Engineering , Worcester Polytechnic Institute , Worcester , Massachusetts 01609 , United States
| | - Yuhan Mei
- Department of Chemical Engineering , Worcester Polytechnic Institute , Worcester , Massachusetts 01609 , United States
| | - Xing Xu
- Department of Chemistry , University of New Hampshire , Durham , New Hampshire 03824 , United States
| | - Anyin Li
- Department of Chemistry , University of New Hampshire , Durham , New Hampshire 03824 , United States
| | - N Aaron Deskins
- Department of Chemical Engineering , Worcester Polytechnic Institute , Worcester , Massachusetts 01609 , United States
| | - Xiaowei Teng
- Department of Chemical Engineering , University of New Hampshire , Durham , New Hampshire 03824 , United States
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Gruzeł G, Arabasz S, Pawlyta M, Parlinska-Wojtan M. Conversion of bimetallic PtNi 3 nanopolyhedra to ternary PtNiSn nanoframes by galvanic replacement reaction. NANOSCALE 2019; 11:5355-5364. [PMID: 30848274 DOI: 10.1039/c9nr01359h] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Hollow multimetallic PtNiSn nanoparticles (NPs) were formed from solid Ni-core/Pt-frame NPs by the galvanic replacement reaction (GRR) of Ni by Sn. The GRR was performed by adding SnCl4·5H2O dissolved in ethylene glycol into the PtNi3 NPs containing suspension. The reaction yielded nanoframes with a hollow interior, having Pt-rich edges covered with a thin, incomplete Sn layer. They were investigated using transmission electron microscopy (TEM), energy dispersion X-ray spectroscopy (EDS) and X-ray diffraction (XRD). EDS analysis showed that the GRR rate could be modified by changing the solvent and the concentration of tin ions. Indeed, compared to water, ethylene glycol was found to facilitate the reduction of tin chloride and to affect nickel dissolution. TEM analysis revealed that the galvanic replacement of nickel and tin involves two different mechanisms. The first one consists of nickel oxidation followed by reduction of tin ions. In the second mechanism, oxidation of nickel and reduction of tin ions occur simultaneously.
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Affiliation(s)
- Grzegorz Gruzeł
- Institute of Nuclear Physics Polish Academy of Sciences, PL-31342 Krakow, Poland.
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Abstract
Pt/C and Pt/SnOx/C catalysts were synthesized using the polyol method. Their structure, morphology and chemical composition were studied using a scanning electron microscope equipped with an energy dispersive X-ray spectrometer, transition electron microscope and X-ray photoelectron spectroscope. Electrochemical measurements were based on the results of rotating disk electrode (RDE) experiments applied to ethanol electrooxidation. The quick evaluation of catalyst activity, electrochemical behavior, and an average number of transferred electrons were made using the RDE technique. The usage of SnOx (through the carbon support modification) in a binary system together with Pt causes a significant increase of the catalyst activity in ethanol oxidation reaction and the utilization of ethanol.
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Zhu F, Tu K, Huang L, Qu X, Zhang J, Liao H, Zhou Z, Jiang Y, Sun S. High selectivity PtRh/RGO catalysts for ethanol electro-oxidation at low potentials: Enhancing the efficiency of CO2 from alcoholic groups. Electrochim Acta 2018. [DOI: 10.1016/j.electacta.2018.08.142] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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