以石墨烯为添加剂,利用一步水热法制备出石墨烯包覆三维花状SnS_2纳米结构,制得的复合纳米材料由石墨烯和数十个纳米薄片组装而得的SnS_2纳米花球构成。利用XRD、SEM等对材料的晶体结构和形貌进行表征,同时研究了其电化学性能。在1 000 ...以石墨烯为添加剂,利用一步水热法制备出石墨烯包覆三维花状SnS_2纳米结构,制得的复合纳米材料由石墨烯和数十个纳米薄片组装而得的SnS_2纳米花球构成。利用XRD、SEM等对材料的晶体结构和形貌进行表征,同时研究了其电化学性能。在1 000 m A/g的电流密度下循环50次后,SnS_2/石墨烯复合材料的可逆容量仍然可达503.1 m Ah/g,容量保持率高达82%。展开更多
Sn-SnSb alloy was synthesized by reducing a aqueous solution containing Sn(Ⅱ) and Sb(Ⅲ) salts with NaBH4 in the presence of sodium citrate. The product was characterized by X-ray diffractometry(XRD) and scanning ele...Sn-SnSb alloy was synthesized by reducing a aqueous solution containing Sn(Ⅱ) and Sb(Ⅲ) salts with NaBH4 in the presence of sodium citrate. The product was characterized by X-ray diffractometry(XRD) and scanning electron microscopy(SEM). Sn-SnSb/graphite composite powders were prepared by mechanical milling and the mass fraction of graphite was increased from 20% to 50%. The effect of graphite content on the electrochemical performance of Sn-SnSb/graphite composite electrode was investigated. The results show the increase of graphite content is in favor of enhancing the first charge-discharge efficiency and improving the cycle performance, but the capacity of the composite electrode decreases with increasing content of graphite.展开更多
目的:寻找可代替锂离子电池负极碳材料的新合金材料,以提高锂离子电池性能。方法:以Hummers法处理的氧化石墨烯为原料,用原位还原法制备石墨烯的同时在其表面上沉积SnSb合金,得到SnSb/石墨烯复合材料。通过X线衍射(X ray diffraction,X...目的:寻找可代替锂离子电池负极碳材料的新合金材料,以提高锂离子电池性能。方法:以Hummers法处理的氧化石墨烯为原料,用原位还原法制备石墨烯的同时在其表面上沉积SnSb合金,得到SnSb/石墨烯复合材料。通过X线衍射(X ray diffraction,XRD)、扫描电子显微镜(scanning electron microscope,SEM)和透射电镜(transmission electron microscope,TEM)等方法对产物进行分析,用恒电流(constant current,CC)充放电、循环伏安(cyclic voltammetry,CV)实验测试了材料的电化学性能。结果:SnSb/复合材料形貌呈现纳米晶与非晶态的混合态,复合材料具有1 349.3 m Ah/g的首次放电比容量,首次库伦效率为58.4%,30次循环后容量仍保持516 m Ah/g。结论:单一SnSb合金的容量衰减较快,而对于SnSb/石墨烯复合材料,细小的合金颗粒均匀包覆在石墨烯的表面,部分改善了颗粒的团聚现象,同时石墨烯可以提高复合材料的导电性能,使材料的循环稳定性得到改善。展开更多
基金supported by the National Natural Science Foundation of China(21575131)the Key Scientific Research Project of High Schools in Henan Province(16A430025,17A480009)~~
文摘以石墨烯为添加剂,利用一步水热法制备出石墨烯包覆三维花状SnS_2纳米结构,制得的复合纳米材料由石墨烯和数十个纳米薄片组装而得的SnS_2纳米花球构成。利用XRD、SEM等对材料的晶体结构和形貌进行表征,同时研究了其电化学性能。在1 000 m A/g的电流密度下循环50次后,SnS_2/石墨烯复合材料的可逆容量仍然可达503.1 m Ah/g,容量保持率高达82%。
基金Project(50542004) supported by the National Natural Science Foundation of ChinaProject(20030533001) supported by the PFDP of the Education Ministry of China
文摘Sn-SnSb alloy was synthesized by reducing a aqueous solution containing Sn(Ⅱ) and Sb(Ⅲ) salts with NaBH4 in the presence of sodium citrate. The product was characterized by X-ray diffractometry(XRD) and scanning electron microscopy(SEM). Sn-SnSb/graphite composite powders were prepared by mechanical milling and the mass fraction of graphite was increased from 20% to 50%. The effect of graphite content on the electrochemical performance of Sn-SnSb/graphite composite electrode was investigated. The results show the increase of graphite content is in favor of enhancing the first charge-discharge efficiency and improving the cycle performance, but the capacity of the composite electrode decreases with increasing content of graphite.
文摘目的:寻找可代替锂离子电池负极碳材料的新合金材料,以提高锂离子电池性能。方法:以Hummers法处理的氧化石墨烯为原料,用原位还原法制备石墨烯的同时在其表面上沉积SnSb合金,得到SnSb/石墨烯复合材料。通过X线衍射(X ray diffraction,XRD)、扫描电子显微镜(scanning electron microscope,SEM)和透射电镜(transmission electron microscope,TEM)等方法对产物进行分析,用恒电流(constant current,CC)充放电、循环伏安(cyclic voltammetry,CV)实验测试了材料的电化学性能。结果:SnSb/复合材料形貌呈现纳米晶与非晶态的混合态,复合材料具有1 349.3 m Ah/g的首次放电比容量,首次库伦效率为58.4%,30次循环后容量仍保持516 m Ah/g。结论:单一SnSb合金的容量衰减较快,而对于SnSb/石墨烯复合材料,细小的合金颗粒均匀包覆在石墨烯的表面,部分改善了颗粒的团聚现象,同时石墨烯可以提高复合材料的导电性能,使材料的循环稳定性得到改善。
