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Abstract Developing eco‐friendly electrochemical devices for electrosynthesis, fuel cells (FCs), and metal‐air batteries (MABs) requires precisely designing the electronic pathway in the oxygen reduction reaction (ORR) process. Understanding the principle of developing low‐cost, highly active, and stable catalysts helps to reduce the usage of noble metals in ORR. Atomically dispersed metal catalysts (ADMCs) emerge as promising alternatives to replace commercial noble metals due to their high utilization of active metal atoms, high intrinsic activity, and controllable coordination environments. In this review, the research tendency and reaction mechanisms in ORR are first summarized. The basic principles concerning the geometric size and chemical coordination of two‐electron ORR (2e−ORR) catalysts were then discussed, aiming to outline the evolution of material design from 2e−ORR to four‐electron ORR (4e−ORR). Subsequently, recent advances in ADMCs primarily investigated for the 4e−ORR are well‐documented. These advances encompass studies on M−N−C coordination, light heteroatom doping, dual‐metal atoms‐based coordination, and interaction between nanoparticle (NPs)/nanoclusters (NCs) and atomically dispersed metals (ADMs). Finally, the setups for 2/4e−ORR applications, key challenges, and opportunities in the future design of ADMCs for the ORR are highlighted.
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Strong precious metal–metal oxide interaction for oxygen reduction reaction: A strategy for efficient catalyst design
Abstract Oxygen reduction reaction (ORR) is an electrochemical reaction in which dissolved oxygen in an electrolyte is reduced to OH−/H2O when receiving electrons. This reaction plays a crucial role in shaping the efficiency of both metal–air batteries and fuel cells, and precious metals are the dominant catalysts carrying out the ORR in their cathodes. However, how to manipulate the electronic structure of precious metals as active sites to further promote ORR performance and maximize the utilization rate is still under development. Metal oxide serves as suitable and promising support that can strongly interact with precious metals for both activity and durability enhancement. Herein, we present recent research updates on strong precious metal–metal oxide interaction (SPMMOI) utilized in ORR. We start by introducing the background of ORR, the issues to be solved, and its practical applications followed by a thorough discussion of the reaction mechanism and comprehensive evaluation protocols of performance. We then provide a complete understanding of the working principle of SPMMOI and highlight the related advances. Finally, we summarize the merits of the precious metal–metal oxide system and propose the research direction as well as some urgent problems to be addressed in the future.
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- PAR ID:
- 10390761
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- SusMat
- Volume:
- 3
- Issue:
- 1
- ISSN:
- 2692-4552
- Page Range / eLocation ID:
- p. 2-20
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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