Issue 42, 2017

Carbon thin-layer-coated manganese oxide nanocrystals as an effective support for high-performance Pt electrocatalysts stabilized at a metal–metal oxide–carbon triple junction

Abstract

The use of the metal-oxide support has been proved to be an effective approach in the development of fuel-cell catalysts especially for improving the stability of Pt-based electrocatalysts, which is not attainable with conventional carbonaceous materials. Nonetheless, because of the intrinsic low electrical conductivity of pure metal-oxides, metal-oxide-supported systems have not been productive in terms of mass activity that is a primary criterion for the cost-effective electrocatalysts. This paper reports the fabrication of a unique Pt/Mn3O4–carbon triple-junction (TJ) structure, bearing a high density of Pt catalysts entirely sandwiched in between the nano-sized Mn3O4 core and surrounding carbon shell, which integrates the complementary advantages of metal-oxide and carbon supports and thus endows Pt catalysts with optimized electrocatalytic performance. In this study, the unexplored capacity of the Mn3O4 surface was found to accelerate the polymerization process of the surface attached dopamine molecule even under an ordinarily unreactive condition, which enabled the formation of a very thin and contiguous polydopamine layer. The resultant polydopamine film could be converted into a 1.8 nm-thin N-doped carbon layer with sufficiently high electrical conductivity, which allowed the Pt deposition during the galvanic replacement reaction to occur exclusively onto the manganese oxide surface covered underneath the carbon layer and therefore produced the TJ of Pt/Mn3O4–carbon. The resultant TJ structure exhibited the 10-fold enhanced mass activity in the oxygen reduction reaction compared with that of the Mn3O4-supported Pt, which is the highest mass activity for the ORR achieved with oxide-supported catalysts that has been reported so far, while preserving the sufficient durability.

Graphical abstract: Carbon thin-layer-coated manganese oxide nanocrystals as an effective support for high-performance Pt electrocatalysts stabilized at a metal–metal oxide–carbon triple junction

Supplementary files

Article information

Article type
Paper
Submitted
16 Aug 2017
Accepted
03 Oct 2017
First published
23 Oct 2017

J. Mater. Chem. A, 2017,5, 22341-22351

Carbon thin-layer-coated manganese oxide nanocrystals as an effective support for high-performance Pt electrocatalysts stabilized at a metal–metal oxide–carbon triple junction

D. Lee, H. Jeong, K. Jeon, L. Zhang, K. Park, S. Ryu, J. Kim and I. S. Lee, J. Mater. Chem. A, 2017, 5, 22341 DOI: 10.1039/C7TA07248A

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements