Hou Xiaojuan, Wang Xianfu, Liu Bin, Wang Qiufan, Luo Tao, Chen Di, Shen Guozhen
Wuhan National Laboratory for Optoelectronics and School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan 430074, China.
Nanoscale. 2014 Aug 7;6(15):8858-64. doi: 10.1039/c4nr01998a.
To solve the reduced output voltage caused by the high lithium redox potential of Co3O4 when applied as an anode material in full cells, an effective strategy is to partially replace Co by Mn to form MnCo2O4 without changing the original crystal structure. Herein, 3D hierarchical MnCo2O4 nanosheets arrays grown via a hydrothermal method on carbon cloths, as binder-free anodes for lithium-ion batteries, exhibit a high areal capacity of 3.0 mA h cm(-2) at a current density of 800 μA cm(-2), excellent cycling stability, good rate performances and a discharge voltage plateau of 0.25 V which is lower than that of their Co3O4 nanosheet counterparts. Due to the increased output voltage of the full cell induced by the introduction of Mn species with a lower lithium extraction potential, MnCo2O4 based full cells display higher or comparative capacity in a certain voltage range compared with Co3O4, while still retaining the excellent conductivity of Co3O4 electrodes. Our work here paves the way for the design of high performance full cells with Co-based oxide electrodes.
为了解决在全电池中用作负极材料时，由于Co3O4的高锂氧化还原电位导致的输出电压降低问题，一种有效的策略是用Mn部分替代Co以形成MnCo2O4，同时不改变其原始晶体结构。在此，通过水热法在碳布上生长的三维分级MnCo2O4纳米片阵列，作为锂离子电池的无粘结剂负极，在800 μA cm(-2)的电流密度下表现出3.0 mA h cm(-2)的高面积容量、优异的循环稳定性、良好的倍率性能以及0.25 V的放电电压平台，该电压平台低于其Co3O4纳米片对应物。由于引入具有较低锂提取电位的Mn物种导致全电池输出电压增加，基于MnCo2O4的全电池在一定电压范围内与Co3O4相比显示出更高或相当的容量，同时仍保留Co3O4电极的优异导电性。我们在此的工作为设计具有Co基氧化物电极的高性能全电池铺平了道路。
