Accelerating Oxygen-Reduction Catalysts through Preventing Poisoning with Non-Reactive Species by Using Hydrophobic Ionic Liquids.

Abstract

Developing cost-effective electrocatalysts for the oxygen reduction reaction (ORR) is a prerequisite for broad market penetration of low-temperature fuel cells. A major barrier stems from the poisoning of surface sites by nonreactive oxygenated species and the sluggish ORR kinetics on the Pt catalysts. Herein we report a facile approach to accelerating ORR kinetics by using a hydrophobic ionic liquid (IL), which protects Pt sites from surface oxidation, making the IL-modified Pt intrinsically more active than its unmodified counterpart. The mass activity of the catalyst is increased by three times to 1.01 A mg(-1) Pt @0.9 V, representing a new record for pure Pt catalysts. The enhanced performance of the IL-modified catalyst can be stabilized after 30 000 cycles. We anticipate these results will form the basis for an unprecedented perspective in the development of high-performing electrocatalysts for fuel-cell applications.

• Authors: Gui-Rong Zhang, Macarena Munoz, Bastian J M Etzold
• Journal: Angewandte Chemie (International ed. in English) (Angew Chem Int Ed Engl) Vol. 55 Issue 6 Pg. 2257-61 (Feb 05 2016) ISSN: 1521-3773 [Electronic] Germany
• PMID: 26668073 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.