Undoubtedly, there remains an urgent prerequisite to achieve significant advances in both the specific capacity and cyclability of Li-O₂ batteries for their practical application. In this work, a series of unique three-dimensional (3D) α-MnO₂/MWCNTs hybrids are successfully prepared using a facile lyophilization method and investigated as the cathode of Li-O₂ batteries. Thereinto, cross-linked α-MnO₂/MWCNTs nanocomposites are first synthesized via a modified chemical route. Results demonstrate that MnO₂ nanorods in the nanocomposites have a length of 100–400 nm and a diameter ranging from 5 to 10 nm, and more attractively, the as-lyophilized 3D MnO₂/MWCNTs hybrids is uniquely constructed with large amounts of interconnected macroporous channels. The Li-O₂ battery with the 3D macroporous hybrid cathode that has a mass percentage of 50% of α-MnO₂ delivers a high discharge specific capacity of 8,643 mAh·g⁻¹ at 100 mA·g⁻¹, and maintains over 90 cycles before the discharge voltage drops to 2.0 V under a controlled specific capacity of 1,000 mAh·g⁻¹. It is observed that when being recharged, the product of toroidal Li₂O₂ particles disappears and electrode surfaces are well recovered, thus confirming a good reversibility. The excellent performance of Li-O₂ battery with the 3D α-MnO₂/MWCNTs macroporous hybrid cathode is ascribed to a synergistic combination between the unique macroporous architecture and highly efficient bi-functional α-MnO₂/MWCNTs electrocatalyst.

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毫无疑问，在实际应用中，要实现Li-O ₂电池的比容量和可循环性方面的重大进步，仍然存在紧迫的先决条件。在这项工作中，一系列独特的三维（3D）α-MnO的₂ /多壁碳纳米管杂交使用的是容易冻干方法成功制备和研究作为李-O阴极_2层的电池。到其中，交联的α-MnO的₂ /多壁碳纳米管的纳米复合材料是通过改性化学路线第一合成。结果表明，纳米复合材料中的MnO ₂纳米棒的长度为100–400 nm，直径为5至10 nm，并且更有吸引力的是，冻干的3D MnO ₂/ MWCNTs杂种具有独特的构造，具有大量相互连接的大孔通道。锂-O ₂电池与具有α-MnO的50％的质量百分比的3D大孔阴极混合₂提供8643毫安·g的高放电比容量^-1以100mA·克^-1，并保持超过90在1,000 mAh·g ^-1的受控比容量下，放电电压下降至2.0 V之前，必须经过一个循环。观察到，当再充电时，环形Li ₂ O ₂颗粒的产物消失并且电极表面被良好地恢复，从而确认了良好的可逆性。带有3Dα-MnO的Li-O ₂电池的出色性能₂ /多壁碳纳米管的大孔阴极混合归因于独特的大孔结构和高效率的双功能α-MnO的之间的协同组合₂ /多壁碳纳米管电催化剂。

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