文章首先采用溶剂热法合成了系列LiMn1-xFexPO4(x=0.15、0.25、0.35、0.45)微纳颗粒,随后采用热分解的方法对微纳颗粒进行碳包覆处理。采用X射线衍射仪(X-ray diffraction,XRD)和扫描电子显微镜(scanning electron microscope,SEM)对微...文章首先采用溶剂热法合成了系列LiMn1-xFexPO4(x=0.15、0.25、0.35、0.45)微纳颗粒,随后采用热分解的方法对微纳颗粒进行碳包覆处理。采用X射线衍射仪(X-ray diffraction,XRD)和扫描电子显微镜(scanning electron microscope,SEM)对微纳颗粒进行表征,结果可知所获微纳颗粒均为橄榄石结构,而LiMn0.75Fe0.25PO4/C分散性较好,颗粒大小较均匀。与LiFePO4/C正极材料相比,LiMn0.75Fe0.25PO4/C的导电性、放电电压、循环稳定性和储锂性能均有明显提高。LiMn0.75Fe0.25PO4/C充放电电压平台为4.1V;在0.5C的电流密度下,首次放电比容量为160mA·h/g,在100圈循环后容量依然保持在140mA·h/g;在10C的电流密度下,保持了60mA·h/g的容量。该文对于研究和发展新型可替代LiFePO4的锂离子电池正极材料具有重要的意义。展开更多
Three metal molybdate hydrates,Fe（H2O） 2（MoO4）2·H3O（FeMo）,NaCo 2（MoO4） 2（H3O2）（CoMo） and Mn 2（MoO4）3·2H3O（MnMo）,were synthesized by the mixed-solvent-thermal methods and characterized by sing...Three metal molybdate hydrates,Fe（H2O） 2（MoO4）2·H3O（FeMo）,NaCo 2（MoO4） 2（H3O2）（CoMo） and Mn 2（MoO4）3·2H3O（MnMo）,were synthesized by the mixed-solvent-thermal methods and characterized by singlecrystal X-ray diffraction.X-Ray photoelectron spectroscopy and bond-valence sums were applied to confirming the valance of Fe,Co,Mn and Mo.Thermo-gravimetric analysis and X-ray powder diffraction measurements indicate that the samples were converted to different structural compounds upon heating in air at 600 ℃ for 1 h.The magnetic properties of these compounds were studied.The dominant magnetic interactions are antiferromagnetic in nature.However,different synthesis conditions led to the diversity of magnetic properties of compound CoMo.展开更多
文摘文章首先采用溶剂热法合成了系列LiMn1-xFexPO4(x=0.15、0.25、0.35、0.45)微纳颗粒,随后采用热分解的方法对微纳颗粒进行碳包覆处理。采用X射线衍射仪(X-ray diffraction,XRD)和扫描电子显微镜(scanning electron microscope,SEM)对微纳颗粒进行表征,结果可知所获微纳颗粒均为橄榄石结构,而LiMn0.75Fe0.25PO4/C分散性较好,颗粒大小较均匀。与LiFePO4/C正极材料相比,LiMn0.75Fe0.25PO4/C的导电性、放电电压、循环稳定性和储锂性能均有明显提高。LiMn0.75Fe0.25PO4/C充放电电压平台为4.1V;在0.5C的电流密度下,首次放电比容量为160mA·h/g,在100圈循环后容量依然保持在140mA·h/g;在10C的电流密度下,保持了60mA·h/g的容量。该文对于研究和发展新型可替代LiFePO4的锂离子电池正极材料具有重要的意义。
基金Supported by the National Natural Science Foundation of China(Nos.20971054,90922034)the Key Project of the Ministry of Education of China(No.2009-49)
文摘Three metal molybdate hydrates,Fe（H2O） 2（MoO4）2·H3O（FeMo）,NaCo 2（MoO4） 2（H3O2）（CoMo） and Mn 2（MoO4）3·2H3O（MnMo）,were synthesized by the mixed-solvent-thermal methods and characterized by singlecrystal X-ray diffraction.X-Ray photoelectron spectroscopy and bond-valence sums were applied to confirming the valance of Fe,Co,Mn and Mo.Thermo-gravimetric analysis and X-ray powder diffraction measurements indicate that the samples were converted to different structural compounds upon heating in air at 600 ℃ for 1 h.The magnetic properties of these compounds were studied.The dominant magnetic interactions are antiferromagnetic in nature.However,different synthesis conditions led to the diversity of magnetic properties of compound CoMo.
