Single-Atom-Based Oxygen Reduction Reaction Catalysts for Proton Exchange Membrane Fuel Cells: Progress and Perspective

Abstract

Single-atom catalysts (SACs) are regarded as promising non-noble-metal alternatives for the oxygen reduction reaction (ORR) in proton exchange membrane fuel cells due to their high atom utilization efficiency and excellent catalytic properties. However, the insufficient long-term stability issues of SACs under the working conditions seriously hinder their practical application. In this perspective, the recent progress of SACs with optimized ORR catalytic activity is first reviewed. Then, the possible degradation mechanisms of SACs in the ORR process and effective strategies for improving their ORR durability are summarized. Finally, some challenges and opportunities are proposed to develop stable single-atom-based ORR electrocatalysts in the future.

Boosting the Performance of Low-Platinum Fuel Cells via a Hierarchical and Interconnected Porous Carbon Support

“…Moreover, the Raman spectrum of the hierarchical porous carbon in Figure S12 shows a sharper G peak around 1560 cm –1 than the D peak around 1380 cm –1 , and this proves that the hierarchical porous carbon is graphitized. Third, the doping elements such as nitrogen and Fe in the hierarchical carbon might have an anchoring effect on the loaded-Pt Figure S13 shows the single-atom state of Fe species in the hierarchical porous carbon.…”

Activity Origin and Catalytic Mechanism of the M–N–C Catalysts for the Oxygen Reduction Reaction

“…M–N–C catalysts have demonstrated appealing performances in rotating disk electrode (RDE) tests and the relevant membrane electrode assembly (MEA). Nevertheless, their stability in ZAB and PEMFC applications is far from satisfied . Although a large number of advanced materials have been developed for MEA, including catalysts, membranes, ionomers, gas diffusion layer (GDL), etc., there are still significant obstacles to integrate these developed materials into actual MEA. − The performance of MEA largely depends on the catalyst activity and electrode fabrication technology .…”

Atomically dispersed Fe/Co–N–C and their composites for proton exchange membrane fuel cells

“…Common degradation mechanisms, including carbon corrosion, demetallation, agglomeration, nitrogen protonation, H 2 O 2 attack, and microporous flooding, have been widely proposed and discussed by some reviews. 171,173–175 Researchers have deeply explored the corresponding strategies to improve stability.…”