Lithium-oxygen batteries have attracted considerable interest in the past a few years, because they have higher theoretical specific energy than Li-ion batteries. However, the available energy densities of the Li-O₂ batteries are much less than expected. It is particularly urgent to find catalyst with high activity. Herein, a series of Co₃O₄ with different morphologies (ordered two-dimensional porous nanosheets, flowerlike and cuboidlike) were successfully prepared through facile hydrothermal and calcination methods. Ordered two-dimensional Co₃O₄ nanosheets show the best cycling stability. Detailed experimental results reveal that the superiority of the unique two-dimensional uniform porous structures is vital for Li-O₂ batteries cathode catalysts. Due to the ordered structures with high surface areas and active sites, the catalysts indicate a high specific discharge capacity of about 10,417 mAh/g at a current density of 200 mA/g, and steadily cycle for more than 50 times with a limited capacity of 1,000 mAh/g.

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在过去的几年中，锂氧电池吸引了相当大的兴趣，因为它们比锂离子电池具有更高的理论比能。但是，Li-O ₂电池的可用能量密度远低于预期。寻找具有高活性的催化剂是特别紧迫的。本文中，通过简便的水热和煅烧方法成功制备了一系列不同形态的Co ₃ O ₄（有序的二维多孔纳米片，花状和长方体状）。有序二维Co ₃ O ₄纳米片显示出最佳的循环稳定性。详细的实验结果表明，独特的二维均匀多孔结构的优越性对于Li-O ₂电池阴极催化剂至关重要。由于具有高表面积和活性位点的有序结构，催化剂在200 mA / g的电流密度下显示出约10,417 mAh / g的高比放电容量，并在50伏特的有限容量下稳定循环超过50次。 1,000 mAh /克。

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