Carbon-Coated Core鈥揝hell Fe鈥揅u Nanoparticles as Highly Active and Durable Electrocatalysts for a Zn鈥揂ir Battery

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• 作者：Gyutae Nam ; Joohyuk Park ; Min Choi ; Pilgun Oh ; Suhyeon Park ; Min Gyu Kim ; Noejung Park ; Jaephil Cho ; Jang-Soo Lee
• 刊名：ACS Nano
• 出版年：2015
• 出版时间：June 23, 2015
• 年：2015
• 卷：9
• 期：6
• 页码：6493-6501
• 全文大小：623K
• ISSN：1936-086X

文摘

Understanding the interaction between a catalyst and oxygen has been a key step in designing better electrocatalysts for the oxygen reduction reaction (ORR) as well as applying them in metal鈥揳ir batteries and fuel cells. Alloying has been studied to finely tune the catalysts鈥?electronic structures to afford proper binding affinities for oxygen. Herein, we synthesized a noble-metal-free and nanosized transition metal CuFe alloy encapsulated with a graphitic carbon shell as a highly efficient and durable electrocatalyst for the ORR in alkaline solution. Theoretical models and experimental results demonstrated that the CuFe alloy has a more moderate binding strength for oxygen molecules as well as the final product, OH^{鈥?/sup>, thus facilitating the oxygen reduction process. Furthermore, the nitrogen-doped graphitic carbon-coated layer, formed catalytically under the influence of iron, affords enhanced charge transfer during the oxygen reduction process and superior durability. These benefits were successfully confirmed by realizing the catalyst application in a mechanically rechargeable Zn鈥揳ir battery.}