کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5432254 | 1508832 | 2017 | 10 صفحه PDF | دانلود رایگان |
To tackle the issues of inferior cycling stability and low intrinsic conductivity for MnO as anode material for lithium ion batteries (LIBs), we design and rationally confine MnO@C core-shell nanorods homogeneously in the flexible graphene matrix via a facile process. The obtained composite exhibits a high reversible capacity (1165.3Â mAh gâ1 at 0.1Â AÂ gâ1), excellent rate capability (618.5Â mAh gâ1 at 2Â AÂ gâ1), and superior cyclability (almost no capacity fading even after 4000 cycles), which has been rarely reported for LIBs. The lithiation and delithiation behavior suggests that the further oxidation of Mn2+ to Mn4+ and the surface pseudocapacitance contribute to the distinctive capacity enhancement. Additionally, the structure reconstruction from MnO nanorods to nanoworm-like and subsequently to nanoparticles achieves faster kinetics of conversion reactions. The excellent rate capability benefits from the presence of 2D dual conductive graphene and amorphous carbon, as well as the synergistic effect between them for elevating the transportation of both lithium ions and electrons. Moreover, the superb cyclic stability can be attributed to the well-defined dual-carbon decoration that alleviates the volume variation as well as the agglomeration and dissolution of MnO, and yields a long-life anode material.
An electrochemical optimal graphene/MnO@C/graphene sandwiched nanohybrid almost addresses all the issues related to MnO as anode materials for LIBs.218
Journal: Carbon - Volume 115, May 2017, Pages 95-104