Kim Eunji, Lee Jeongmin, Park Junghyun, Kim Heejin, Nam Kwan Woo
Department of Chemical Engineering and Materials Science, and Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul 03760, Republic of Korea.
Division of Analytical Science, Korea Basic Science Institute, 169-148 Gwahak-ro, Daejeon 34133, Republic of Korea.
Nano Lett. 2025 Jan 15;25(2):619-627. doi: 10.1021/acs.nanolett.4c03482. Epub 2025 Jan 6.
Spinel lithium manganese oxide (LiMnO, LMO) is a promising cathode material with nontoxicity, high operating voltage, and low cost. However, structural collapse during battery cycling ─ caused by Mn dissolution and the Jahn-Teller effect ─ is a critical disadvantage, reducing cycle retention, particularly at high temperatures. In this study, to solve these critical issues, we introduce Cu(HITP) (CuHITP; HITP = 2,3,6,7,10,11-hexaiminotriphenylene), a conductive two-dimensional (2D) metal-organic framework (MOF) as a surface coating material. The CuHITP-derived coating increases the electrical conductivity and suppresses Mn dissolution by enriching the LMO surface with Mn. By suppressing Mn dissolution, structural stability also improves, offsetting the inherent problems. As a result, at 60 °C, CuHITP-LMO exhibits an initial capacity of 95.8 mAh g at 100 mA g and achieves a capacity of 42.4 mAh g after 300 cycles. This research highlights the potential of conductive 2D MOFs to improve the electrochemical performances of LMO.
尖晶石型锂锰氧化物（LiMnO，LMO）是一种很有前景的正极材料，具有无毒、工作电压高和成本低的特点。然而，电池循环过程中的结构坍塌——由锰溶解和 Jahn-Teller 效应引起——是一个关键缺点，会降低循环保持率，尤其是在高温下。在本研究中，为了解决这些关键问题，我们引入了 Cu(HITP)（CuHITP；HITP = 2,3,6,7,10,11-六亚氨基三亚苯），一种导电二维（2D）金属有机框架（MOF）作为表面涂层材料。源自 CuHITP 的涂层通过用锰富集 LMO 表面来提高电导率并抑制锰溶解。通过抑制锰溶解，结构稳定性也得到改善，从而抵消了固有问题。结果，在 60°C 下，CuHITP-LMO 在 100 mA g 时的初始容量为 95.8 mAh g，300 次循环后容量达到 42.4 mAh g。这项研究突出了导电二维 MOF 在改善 LMO 电化学性能方面的潜力。
