CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology , Beijing 100190, P. R. China.
Department of Environment and Chemical Engineering, Yanshan University , Qinhuangdao 066004, P. R. China.
ACS Appl Mater Interfaces. 2017 Dec 13;9(49):43171-43178. doi: 10.1021/acsami.7b15315. Epub 2017 Nov 30.
Metal-organic frameworks (MOFs) are hybrid inorganic-organic materials that can be used as effective precursors to prepare various functional nanomaterials for energy-related applications. Nevertheless, most MOF-derived metal oxides exhibit low electrical conductivity and mechanical strain. These characteristics limit their electrochemical performance and hamper their practical application. Herein, we report a rational strategy for enhancing the lithium storage performance of MOF-derived metal oxide. The hierarchically porous CoO@NGN is successfully prepared by embedding ZIF-67-derived CoO particles in a nitrogen-doped graphene network (NGN). The high electrical conductivity and porous structure of the NGN accelerates the diffusion of electrolyte ions and buffers stress resulting from the volume changes of CoO. As an anode material, the CoO@NGN shows high capacity (1030 mA h g at 100 mA g), outstanding rate performance (681 mA h g at 1000 mA g), and good cycling stability (676 mA h g at 1000 mA g after 400 cycles).
金属-有机骨架(MOFs)是一种杂化的无机-有机材料,可用作制备各种用于能源相关应用的功能纳米材料的有效前体。然而,大多数 MOF 衍生的金属氧化物表现出低电导率和机械应变。这些特性限制了它们的电化学性能,并阻碍了它们的实际应用。在此,我们报告了一种增强 MOF 衍生金属氧化物储锂性能的合理策略。通过将 ZIF-67 衍生的 CoO 颗粒嵌入氮掺杂石墨烯网络(NGN)中,成功制备了具有分级多孔结构的 CoO@NGN。NGN 的高导电性和多孔结构加速了电解质离子的扩散,并缓冲了 CoO 体积变化引起的应力。作为一种阳极材料,CoO@NGN 表现出高容量(在 100 mA g 时为 1030 mA h g)、优异的倍率性能(在 1000 mA g 时为 681 mA h g)和良好的循环稳定性(在 1000 mA g 下循环 400 次后为 676 mA h g)。