原料浓度比对T型微反应器共沉淀制备多孔一氧化锰/碳的影响

Influence of concentration ratio on preparation of MnO/C by co-precipitation in T-shaped microchannel reactor

以一水合硫酸锰、碳酸氢铵为原料,采用T型微反应器共沉淀法制备了球形碳酸锰,以该碳酸锰为前驱体,蔗糖为碳源煅烧后得到球形多孔一氧化锰/碳锂离子电池负极材料。利用X射线衍射(XRD)、扫描电镜(SEM)、氮气吸附-脱附曲线、恒电流充放电测试、交流阻抗(EIS)和循环伏安(CV)等方法研究了原料浓度比对一氧化锰/碳电极材料的结构、形态和电化学性能的影响。结果表明,首次放电比容量可以达到1 129.69 m A·h/g,第二圈的放电比容量为707.03 m A·h/g,接近于理论比容量,循环50圈以后,容量仍可以保持在576.93 m A·h/g,显示出较好的电化学性能。

MnCO3 microspheres were prepared by coprecipitation method in a T-type microreactor with MnSO4· H2O and NH4HCO3 as raw materials.Spherical porous MnO/C lithium ion battery anode material was obtained after calcination with the prepared MnCO3 microspheres as the precursor and with the sucrose as the carbon source.The influences of raw material concentration ratio on the structure, morphology, and electrochemical properties of the MnO/C electrode materials were investigated by X-ray diffraction （XRD）,scanning electron microscopy （SEM）,nitrogen adsorption and desorption isotherms ,galvanostatic charge-discharge cycling, impedance spectra （EIS）, and cyclic voltammetry （CV） etc..Results showed that the initial discharge capacity could reach 1 129.69 mA· h/g, the second cycle discharge capacity was close to the theoretical specific which was 707.03 mA·h/g. After cycling 50 cycles,the capacity could still be maintained at 576.93 mA ·h/g,which showed good electrochemical performance.