【摘要】 使用通过简单加热聚丙烯腈(PAN)和硫单质而得到的导电含硫材料(conductive sulfur-containing material,CSM)及其与聚苯胺(PAn)的复合物作为镁二次电池的正极材料.X射线衍射(XRD)和傅立叶红外光谱(FT-IR)测试表明,导电含硫材料的结构由类似石墨的微晶相及无定形相所组成,材料骨架为含有S—S键的脱水嘧啶型基质.该导电含硫材料与聚苯胺复合并掺杂Cu(II)后,其放电比容量和电化学可逆性大大提高,放电比容量可达117.3mAh·g-1,22次循环后容量保持大约78%(相对于第二次放电容量).聚苯胺不仅起到电化学催化剂的作用,同时也是电极活性物质,并且在分子水平上改善了活性材料的导电性能.该复合物研究结果为镁二次电池正极材料结构设计的开发提供了新的思路.更多还原

【Abstract】 Conductive sulfur-containing material(CSM),synthesized by simply heating a mixture of polyacrylonitrile(PAN)and elemental sulfur,and its composite with polyaniline(PAn)were used as the cathode material for rechargeable magnesium batteries.X-ray diffraction(XRD)and Fourier-transform infrared(FT-IR)spectroscopy measurements showed that the CSM consisted of a graphite-like microcrystal phase and an amorphous phase,with a dehydrapyrimidine-type matrix containing S-S bonds.When polyaniline was incorporated with CSM and Cu(II)was doped into the CSM/PAn composite,the specific discharge capacity and electrochemical reversibility were enhanced significantly.The composite exhibited a discharge capacity of 117.3 mAh·g-1 and the capacity retention remained at about 78% after twenty-two cycles,based on the second cycle discharge capacity.Here PAn functioned as both electrocatalyst and cathode material.At the same time,it improved the conductivity of the active CSM at a molecular level.The results of this study provided a new thought for structure design and development of a potential cathode material for rechargeable magnesium batteries.更多还原