Alkaline direct alcohol fuel cells (ADAFCs) represent an attractive alternative to hydrogen fuel cells for the more convenient storage, transportation, and lower cost of alcohols (e.g., methanol and ethanol) when compared with compressed hydrogen. However, the anode alcohol oxidation reaction (AOR) is generally plagued with high overpotential and sluggish kinetics, and often requires noble metal‐based electrocatalysts to accelerate the reaction kinetics. To this end, the development of efficient AOR electrocatalysts with high mass activity (MA), high durability, high Faradaic efficiency (FE), and low overpotential is central for realizing practical ADAFCs. Here, in this minireview, a brief introduction of the fundamental challenges associated with AOR in alkaline electrolyte, the key performance metrics, and the evaluation protocols for benchmarking AOR electrocatalysts are presented, followed by a summary of the recent advances in the noble‐metal based AOR electrocatalysts (e.g., Pt, Pd, and Rh) with an emphasis on the design criteria for improving the specific activity and electrochemical surface area to ultimately deliver high MA while at the same time ensuring long term durability. The strategies to enhance FE and lower overpotential will also be discussed. Last, it is concluded with a brief perspective on the key challenges and future opportunities.
The key in designing efficient direct liquid fuel cells (DLFCs), which can offer some solutions to society's grand challenges associated with sustainability and energy future, currently lies in the development of cost‐effective electrocatalysts. Among the many types of fuel cells, direct hydrazine fuel cells (DHFCs) are of particular interest, especially due to their high theoretical cell voltages and clean emission. However, DHFCs currently use noble‐metal‐based electrocatalysts, and the scarcity and high cost of noble metals are hindering these fuel cells from finding large‐scale practical applications. In order to replace noble‐metal‐based electrocatalysts with sustainable ones and help DHFCs become widely usable, great efforts are being made to develop stable heteroatom (e.g., B, N, O, P and S)‐doped carbon electrocatalysts, the activities of which are comparable to, or better than, those of noble metals. Here, the recent research progress and the advancements made on the development of heteroatom‐doped carbon materials, their general properties, their electrocatalytic activities toward the HzOR, and their dopant‐ and structure‐related electrocatalytic properties for the HzOR are summarized. Perspectives on the different directions that the research endeavors in this field need to take in the future and the challenges associated with DHFCs are included.
more » « less- NSF-PAR ID:
- 10461909
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials
- Volume:
- 31
- Issue:
- 13
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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