Realising the activity benefits of Pt preferential (111) surfaces for ethanol oxidation in a nanowire electrocatalyst
Realising the activity benefits of Pt preferential (111) surfaces for ethanol oxidation in a nanowire electrocatalyst
The commercialisation of direct ethanol fuel cells (DEFCs) is hindered by the low activity of the currently available electrocatalysts that are mainly carbon-supported nanoparticles (NPs). Here, we synthesised carbon-supported Pt nanowires (Pt/C NWs) by chemical reduction of metallic precursors at room temperature without using surfactants, templates, or stabilising agents. The synthesised Pt NWs were supported on high surface area carbon (Vulcan XC-72R) with 40 wt%. of metal loading concerning the support. The electroactivity of the synthesised NWs catalyst towards ethanol and CO (the dominant intermediate species) oxidation is investigated and tested in comparison with a commercial nanoparticle Pt/C electrocatalyst (named: Pt/C NPs). The electrooxidation of ethanol was investigated in acid media by COstripping, cyclic voltammetry, derivative voltammetry, chronoamperometry, steady-state polarisation curves, and in situ Fourier transform infrared spectroscopy (FTIR) experiments. The results showed that the synthesised Pt NWs are much more active than the Pt/C NPs catalyst, for both ethanol and CO-monolayer oxidation in acidic media. In situ FTIR data revealed that Pt NWs catalyst favours the formation of CO2 and acetic acid. This activity is mainly due to the existence of extended terraces, resulting in enhanced mobility of OHads and COads, facilitating the removal of COads from the catalyst surface and allowing better ethanol adsorption for further oxidation. Hence, 5-fold higher current density for ethanol oxidation is obtained. The NW morphology of Pt nanocatalysts results in very active materials towards ethanol oxidation and may provide a promising means of increasing the performance of anodes for DEFCs.
adsorption, current density, ethanol electro-oxidation, nanowires
Sebadelhe Valerio Neto, Edmundo
6eb07b6c-5753-42f1-83ae-1745ecbc0773
Almeida, Caio V.S.
718ae32a-23a1-4a8d-8248-a66d6f96f5fc
Russell, Andrea E.
b6b7c748-efc1-4d5d-8a7a-8e4b69396169
Salazar-Banda, Giancarlo R.
80800367-cb82-42ad-8137-83e98dbf4ecb
Eguiluz, Katlin I.B.
59d40318-d101-44e0-b00c-b8f30aa1baf4
10 July 2020
Sebadelhe Valerio Neto, Edmundo
6eb07b6c-5753-42f1-83ae-1745ecbc0773
Almeida, Caio V.S.
718ae32a-23a1-4a8d-8248-a66d6f96f5fc
Russell, Andrea E.
b6b7c748-efc1-4d5d-8a7a-8e4b69396169
Salazar-Banda, Giancarlo R.
80800367-cb82-42ad-8137-83e98dbf4ecb
Eguiluz, Katlin I.B.
59d40318-d101-44e0-b00c-b8f30aa1baf4
Sebadelhe Valerio Neto, Edmundo, Almeida, Caio V.S., Russell, Andrea E., Salazar-Banda, Giancarlo R. and Eguiluz, Katlin I.B.
(2020)
Realising the activity benefits of Pt preferential (111) surfaces for ethanol oxidation in a nanowire electrocatalyst.
Electrochimica Acta, 348, [136206].
(doi:10.1016/j.electacta.2020.136206).
Abstract
The commercialisation of direct ethanol fuel cells (DEFCs) is hindered by the low activity of the currently available electrocatalysts that are mainly carbon-supported nanoparticles (NPs). Here, we synthesised carbon-supported Pt nanowires (Pt/C NWs) by chemical reduction of metallic precursors at room temperature without using surfactants, templates, or stabilising agents. The synthesised Pt NWs were supported on high surface area carbon (Vulcan XC-72R) with 40 wt%. of metal loading concerning the support. The electroactivity of the synthesised NWs catalyst towards ethanol and CO (the dominant intermediate species) oxidation is investigated and tested in comparison with a commercial nanoparticle Pt/C electrocatalyst (named: Pt/C NPs). The electrooxidation of ethanol was investigated in acid media by COstripping, cyclic voltammetry, derivative voltammetry, chronoamperometry, steady-state polarisation curves, and in situ Fourier transform infrared spectroscopy (FTIR) experiments. The results showed that the synthesised Pt NWs are much more active than the Pt/C NPs catalyst, for both ethanol and CO-monolayer oxidation in acidic media. In situ FTIR data revealed that Pt NWs catalyst favours the formation of CO2 and acetic acid. This activity is mainly due to the existence of extended terraces, resulting in enhanced mobility of OHads and COads, facilitating the removal of COads from the catalyst surface and allowing better ethanol adsorption for further oxidation. Hence, 5-fold higher current density for ethanol oxidation is obtained. The NW morphology of Pt nanocatalysts results in very active materials towards ethanol oxidation and may provide a promising means of increasing the performance of anodes for DEFCs.
Text
EA19-8458R2
- Accepted Manuscript
Restricted to Repository staff only
Request a copy
Text
1-s2.0-S0013468620305983-main
- Accepted Manuscript
More information
Accepted/In Press date: 6 April 2020
e-pub ahead of print date: 9 April 2020
Published date: 10 July 2020
Additional Information:
Funding Information:
The authors would like to thank CNPq (grants: 305438/2018–2 , 407274/2013–8 , 400443/2013–9 , 474261/2013–1 , 304419/2015–0 , and 310282/2013–6 ), to the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES (grant: 88881.121097/2016–01 ), to FAPITEC/SE , Brazil, and The Royal Society and the Newton Fund ( NMG∖R1∖180416 - Newton Mobility Grants 2018 Round 1) for financial support and scholarships.
Publisher Copyright:
© 2020 Elsevier Ltd
Keywords:
adsorption, current density, ethanol electro-oxidation, nanowires
Identifiers
Local EPrints ID: 439650
URI: http://eprints.soton.ac.uk/id/eprint/439650
ISSN: 0013-4686
PURE UUID: a8933748-8bd0-47f8-8cfa-adb7f4114511
Catalogue record
Date deposited: 29 Apr 2020 16:30
Last modified: 17 Mar 2024 05:30
Export record
Altmetrics
Contributors
Author:
Edmundo Sebadelhe Valerio Neto
Author:
Caio V.S. Almeida
Author:
Giancarlo R. Salazar-Banda
Author:
Katlin I.B. Eguiluz
Download statistics
Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.
View more statistics
