Details

Autor(en) / Beteiligte

• Zhao, Zipeng
• Hossain, Md Delowar
• Xu, Chunchuan
• Lu, Zijie
• Liu, Yi-Sheng
• Hsieh, Shang-Hsien
• Lee, Ilkeun
• Gao, Wenpei
• Yang, Jun
• Merinov, Boris V.
• Xue, Wang
• Liu, Zeyan
• Zhou, Jingxuan
• Luo, Zhengtang
• Pan, Xiaoqing
• Zaera, Francisco
• Guo, Jinghua
• Duan, Xiangfeng
• Goddard, William A.
• Huang, Yu

Titel

Tailoring a Three-Phase Microenvironment for High-Performance Oxygen Reduction Reaction in Proton Exchange Membrane Fuel Cells

Ist Teil von

• Matter, 2020-11, Vol.3 (5), p.1774-1790

Ort / Verlag

United States: Elsevier Inc

Erscheinungsjahr

2020

Link zum Volltext

Quelle

Free E-Journal (出版社公開部分のみ）

Beschreibungen/Notizen

• Despite tremendous progress in catalyst development for rate-limiting cathodic oxygen reduction reaction (ORR), reducing Pt usage while meeting performance requirements in practical proton exchange membrane fuel cells (PEMFCs) remains a challenge. The ORR in PEMFCs occurs at a catalyst–electrolyte–gas three-phase interface. A desirable interface should exhibit highly active and available catalytic sites, as well as allow efficient oxygen and proton feeding to the catalytic sites and timely removal of water to avoid interface flooding. Here, we report the design of a three-phase microenvironment in PEFMCs, showing that carbon surface chemistry can be tuned to modulate its interaction with the ionomers and create favorable transport paths for rapid delivery of both reactants and products. With such an elaborate interfacial design, for the first time we have demonstrated PEMFCs with all key ORR catalyst performance metrics, including mass activity, rated power, and durability, surpassing the US Department of Energy targets. [Display omitted] •Carbon support surface can be manipulated to create a desirable reaction interface•Mass transport in PEMFCs is improved via carbon support engineering•Pt-based catalyst on improved carbon support showing outstanding performance in MEA The rate-limiting cathodic oxygen reduction reaction (ORR) in proton exchange membrane fuel cells (PEMFCs) occurs at a catalyst-electrolyte-gas three-phase interface. A desirable interface should exhibit not only highly active and available catalytic sites, but also efficient mass transfer to allow timely reactant feeding and timely product removal. In this study, we demonstrate that carbon support surface chemistry can be tuned to modulate its interaction with the ionomers and hence create a favorable environment to facilitate ORR in membrane electrode assembly (MEA), and also demonstrate that the MEAs built with such a catalyst/support interface can deliver a performance surpassing the targets set by the US Department of Energy in terms of mass activity, stability, and rated power. This work demonstrates and highlights the importance of engineering a support–electrolyte interface to improve ORR in a realistic environment. The oxygen reduction reaction (ORR) in proton exchange membrane fuel cells (PEMFCs) is sluggish and demands high use of Pt-catalysts, which drives up the system cost and limits its mass applications. Facilitating the ORR in PEMFCs, which occurs at a catalyst–electrolyte–gas three-phase interface, requires both active catalyst and efficient mass transport; however, reports on the latter are limited. This work demonstrates high PEMFC performances by creating a desirable ORR interface by engineering the surface of carbon supports.