| The commercial lithium ion batteries（LIBs） usually adopt the graphite as the anode materials. However, it often suffers from low rate performance, diffusion coefficient, and theoretical capacity. Therefore, it cannot meet the current demand for the use of electrical equipments in new energy storage power system. In order to make full use of LIBs as mobile power supplies, high capacity, safety and good cycle performance anode materials has been becoming the current hot. Metal–organic framework（MOF） materials have many advantages, such as high specific surface area, easy functionalization, high chemical stability and superior catalytic properties. So the application of MOF materials in many areas is proving broad prospects.In this thesis, we synthesized core-shell hierarchical multitunnelled network of Fe4[Fe（CN）6]3@Co3[Co（CN）6]2 and pure Co3[Co（CN）6]2 materials under hydrothermal conditions. The structure and phase composition were characterized by PXRD, SEM, TEM, FT-IR, XPS and so on. In order to test the electrochemical properties under different conditions, we assemble the as-prepared materials with lithium metal piece into half-cell. To investigate the processes of Li storage performance of Fe4[Fe（CN）6]3@Co3[Co（CN）6]2, the phase and morphology of Fe4[Fe（CN）6]3@Co3[Co（CN）6]2 during the charge/discharge processes were analyzed with XPS, TEM, FT-IR and XRD measurements. We put forward to Li storage mechanism of MOF materials by these experiments.The main research contents are as follows:（1）Synthesis of Co3[Co（CN）6]2 under solvothermal conditions.Co3[Co（CN）6]2 were prepared via solvothermal method by using PVP as surfactant and K3[Co（CN）6] as raw material. Co3[Co（CN）6]2 exhibit excellent electrochemical lithium storage performance. After 100 cycles, the as-prepared electrodes deliver a high specific capacity of 643.7 m A h g-1.（2）Synthesis of Fe4[Fe（CN）6]3@Co3[Co（CN）6]2 microcubes under hydrothermal conditions and Li storage mechanism.With K3[Co（CN）6] and K4[Fe（CN）6] as raw materials, Fe4[Fe（CN）6]3@Co3[Co（CN）6]2 microcubes were prepared via hydrothermal method with PVP as surfactant. Under acid condition, K4[Fe（CN）6] first reacts with as-dissociated Fe3+ to form Fe4[Fe（CN）6]3. With the increase of the hydrothermal temperature, K3[Co（CN）6] converts into Co3[Co（CN）6]2 on the surface of Fe4[Fe（CN）6]3. So core-shell Fe4[Fe（CN）6]3@Co3[Co（CN）6]2 was obtained. Fe4[Fe（CN）6]3@Co3[Co（CN）6]2 as an anode exhibits excellent electrochemical lithium storage performance. After 100 cycles, the as-prepared electrodes deliver a high specific capacity of 783.7 m A h g-1 at current density of 100 mA g-1. |
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