Wu Kunze, Zhang Lei, Yuan Yifei, Zhong Linxin, Chen Zhongxin, Chi Xiao, Lu Hao, Chen Zehong, Zou Ren, Li Tingzhen, Jiang Chengyu, Chen Yongkang, Peng Xinwen, Lu Jun
State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou, 510641, China.
Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, IL, 60439, USA.
Adv Mater. 2020 Aug;32(32):e2002292. doi: 10.1002/adma.202002292. Epub 2020 Jul 1.
Mechanically stable and foldable air cathodes with exceptional oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) activities are key components of wearable metal-air batteries. Herein, a directional freeze-casting and annealing approach is reported for the construction of a 3D honeycomb nanostructured, N,P-doped carbon aerogel incorporating in situ grown FeP/Fe O nanoparticles as the cathode in a flexible Zn-air battery (ZAB). The aqueous rechargeable Zn-air batteries assembled with this carbon aerogel exhibit a remarkable specific capacity of 648 mAh g at a current density of 20 mA cm with a good long-term durability, outperforming those assembled with commercial Pt/C+RuO catalyst. Furthermore, such a foldable carbon aerogel with directional channels can serve as a freestanding air cathode for flexible solid-state Zn-air batteries without the use of carbon paper/cloth and additives, giving a specific capacity of 676 mAh g and an energy density of 517 Wh kg at 5 mA cm together with good cycling stability. This work offers a new strategy to design and synthesize highly effective bifunctional air cathodes to be applied in electrochemical energy devices.
具有优异氧还原反应（ORR）和析氧反应（OER）活性的机械稳定且可折叠的空气阴极是可穿戴金属空气电池的关键组件。在此，报道了一种定向冷冻铸造和退火方法，用于构建一种三维蜂窝状纳米结构的N、P掺杂碳气凝胶，其中原位生长有FeP/Fe₃O₄纳米颗粒，用作柔性锌空气电池（ZAB）的阴极。用这种碳气凝胶组装的水系可充电锌空气电池在电流密度为20 mA cm⁻²时表现出648 mAh g⁻¹的显著比容量，具有良好的长期耐久性，优于用商业Pt/C+RuO₂催化剂组装的电池。此外，这种具有定向通道的可折叠碳气凝胶可以用作柔性固态锌空气电池的独立空气阴极，无需使用碳纸/布和添加剂，在5 mA cm⁻²时比容量为676 mAh g⁻¹，能量密度为517 Wh kg⁻¹，同时具有良好的循环稳定性。这项工作为设计和合成应用于电化学能量装置的高效双功能空气阴极提供了一种新策略。
