以玉米芯为碳源的碳/硫复合正极材料的制备和研究

Preparation and performance of the carbon/sulfur compound anode materials with corn cob as carbon source

采用磷酸活化法制备玉米芯活性炭,并将其与单质硫热复合制备了碳/硫正极复合材料。通过XRD、BET、SEM等材料分析测试手段,对材料的物理化学性能进行了分析,利用循环伏安和电池充放电对材料的电化学性能进行了测试。测试结果表明,玉米芯活性炭能抑制多硫化物的溶解,减少活性物质硫的损失,从而提高碳/硫复合材料的放电比容量和循环性能。在0.2mA/cm2的电流下首次放电比容量高达761.2mAh/g,循环20次后放电比容量仍有683.2mAh/g,容量保持率达89.75%。

Carbon/sulfur compound materials was prepared by heating elemental sulfur and corn cob activated carbon which was prepared by phosphoric acid activation method.The physics performance was characterized by XRD,BET and SEM.The electrochemical performance of carbon/ sulfur compound materials was characterized by CV and charge/discharge experiment.The results indicated that the corn cob activated carbon could inhibit the dissolution of polysulfides,reduce the loss of the active substance sulfur,so that discharge specific capacity of the carbon/sulfur composite material and cycle performance were improved.The specific capacity was 761.2mAh/g in the first cycle under the current density of 0.2mA/cm2,and the specific capacity still keep as high as 683.2mAh/g,after 20cycles just fade by 10.25%.