Li Longbin, Tang Xiannong, Wu Bing, Huang Bingyu, Yuan Kai, Chen Yiwang
College of Chemistry and Chemical Engineering, Gannan Normal University, Ganzhou, 341000, China.
College of Chemistry and Chemical Engineering/Institute of Polymers and Energy Chemistry (IPEC)/Jiangxi Provincial Key Laboratory of New Energy Chemistry, Nanchang University, Nanchang, 330031, China.
Adv Mater. 2024 Mar;36(13):e2308326. doi: 10.1002/adma.202308326. Epub 2024 Jan 12.
The air electrode is an essential component of air-demanding energy storage/conversion devices, such as zinc-air batteries (ZABs) and hydrogen fuel cells (HFCs), which determines the output power and stability of the devices. Despite atom-level modulation in catalyst design being recently achieved, the air electrodes have received much less attention, causing a stagnation in the development of air-demanding equipment. Herein, the evolution of air electrodes for ZABs and HFCs from the early stages to current requirements is reviewed. In addition, the operation mechanism and the corresponding electrocatalytic mechanisms of ZABs are summarized. In particular, by clarifying the air electrode interfaces of ZABs at different scales, several approaches to improve the air electrode in rechargeable ZABs are reviewed, including innovative electrode structures and bifunctional oxygen catalysts. Afterward, the operating mechanisms of proton-exchange-membrane fuel cells (PEMFCs) and anion-exchange-membrane fuel cells (AEMFCs) are explained. Subsequently, the strategies employed to enhance the efficiency of the membrane electrode assembly (MEA) in PEMFCs and AEMFCs, respectively, are highlighted and discussed in detail. Last, the prospects for air electrodes in ZABs and HFCs are considered by discussing the main challenges. The aim of this review is to facilitate the industrialization of ZABs and HFCs.
空气电极是诸如锌空气电池（ZAB）和氢燃料电池（HFC）等需氧储能/转换装置的关键组件，它决定了这些装置的输出功率和稳定性。尽管最近在催化剂设计方面已实现原子级调制，但空气电极受到的关注却少得多，导致需氧设备的发展停滞不前。在此，本文综述了ZAB和HFC的空气电极从早期阶段到当前要求的演变。此外，还总结了ZAB的运行机制及相应的电催化机制。特别地，通过阐明不同尺度下ZAB的空气电极界面，综述了几种改进可充电ZAB中空气电极的方法，包括创新的电极结构和双功能氧催化剂。随后，解释了质子交换膜燃料电池（PEMFC）和阴离子交换膜燃料电池（AEMFC）的运行机制。接着，分别重点介绍并详细讨论了用于提高PEMFC和AEMFC中膜电极组件（MEA）效率的策略。最后，通过讨论主要挑战来展望ZAB和HFC中空气电极的前景。本综述的目的是推动ZAB和HFC的工业化进程。
