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Nano Research 2016, 9(6): 1831-1843 https://doi.org/10.1007/s12274-016-1076-z
Research Article | Issue | Published: 28 April 2016

Multicomponent platinum-free nanoporous Pd-based alloy as an active and methanol-tolerant electrocatalyst for the oxygen reduction reaction

Show Author's Information Xiaoting Chen1,§,  Conghui Si1,§,  Ying Wang1,  Yi Ding2,  Zhonghua Zhang1( )
Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education)School of Materials Science and Engineering, Shandong University, Jingshi Road 17923Jinan250061China
School of Materials Science and EngineeringTianjin University of Technology, 391 Binshui Xidao, Xiqing DistrictTianjin300384China

§ These authors contributed equally to this work.

Keywords:
oxygen reduction reaction, dealloying, electrocatalyst, methanol tolerance, direct methanol fuel cells, nanoporous alloys
Cite this article:
Chen X, Si C, Wang Y, et al. Multicomponent platinum-free nanoporous Pd-based alloy as an active and methanol-tolerant electrocatalyst for the oxygen reduction reaction. Nano Research, 2016, 9(6): 1831-1843. https://doi.org/10.1007/s12274-016-1076-z
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Abstract Full text About this article

Development of high-performance oxygen reduction reaction (ORR) catalysts is crucial to improve proton exchange membrane fuel cells. Herein, a multicomponent nanoporous PdCuTiAl (np-PdCuTiAl) electrocatalyst has been synthesized by a facile one-step dealloying strategy. The np-PdCuTiAl catalyst exhibits a three-dimensional bicontinuous interpenetrating ligament/channel structure with an ultrafine length scale of ~3.7 nm. The half-wave potential of np PdCuTiAl is 0.873 V vs. RHE, more positive than those of PdC (0.756 V vs. RHE) and PtC (0.864 V vs. RHE) catalysts. The np-PdCuTiAl alloy shows a 4-electron reaction pathway with similar Tafel slopes to PtC. Remarkably, the half-wave potential shows a negative shift of only 12 mV for np-PdCuTiAl in the presence of methanol, and this negative shift is much lower than those of the PdC (50 mV) and PtC (165 mV) catalysts. The enhanced ORR activity of np-PdCuTiAl has been further rationalized through density functional theory calculations.


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About this article

Multicomponent platinum-free nanoporous Pd-based alloy as an active and methanol-tolerant electrocatalyst for the oxygen reduction reaction

Show Author's information Xiaoting Chen1,§, Conghui Si1,§, Ying Wang1, Yi Ding2, Zhonghua Zhang1( )
Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education)School of Materials Science and Engineering, Shandong University, Jingshi Road 17923Jinan250061China
School of Materials Science and EngineeringTianjin University of Technology, 391 Binshui Xidao, Xiqing DistrictTianjin300384China

§ These authors contributed equally to this work.

Abstract

Development of high-performance oxygen reduction reaction (ORR) catalysts is crucial to improve proton exchange membrane fuel cells. Herein, a multicomponent nanoporous PdCuTiAl (np-PdCuTiAl) electrocatalyst has been synthesized by a facile one-step dealloying strategy. The np-PdCuTiAl catalyst exhibits a three-dimensional bicontinuous interpenetrating ligament/channel structure with an ultrafine length scale of ~3.7 nm. The half-wave potential of np PdCuTiAl is 0.873 V vs. RHE, more positive than those of PdC (0.756 V vs. RHE) and PtC (0.864 V vs. RHE) catalysts. The np-PdCuTiAl alloy shows a 4-electron reaction pathway with similar Tafel slopes to PtC. Remarkably, the half-wave potential shows a negative shift of only 12 mV for np-PdCuTiAl in the presence of methanol, and this negative shift is much lower than those of the PdC (50 mV) and PtC (165 mV) catalysts. The enhanced ORR activity of np-PdCuTiAl has been further rationalized through density functional theory calculations.

Keywords: oxygen reduction reaction, dealloying, electrocatalyst, methanol tolerance, direct methanol fuel cells, nanoporous alloys

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Publication history
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Acknowledgements

Publication history

Received: 06 August 2015
Revised: 14 March 2016
Accepted: 16 March 2016
Published: 28 April 2016
Issue date: June 2016

Copyright

© Tsinghua University Press and Springer-Verlag Berlin Heidelberg 2016

Acknowledgements

Acknowledgements

The authors gratefully acknowledge financial support by National Basic Research Program of China (973, No. 2012CB932800), National Natural Science Foundation of China (No. 51371106), Specialized Research Fund for the Doctoral Program of Higher Education of China (No. 20120131110017), Cross Disciplinary Training Project of Shandong University (No. 2014JC004), and Young Tip-top Talent Support Project (the Organization Department of the Central Committee of the CPC). Z. H. Z. also acknowledges the support from the Alexander von Humboldt Foundation, Germany.

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