CAJ | 학술논문

采用溶胶?凝胶法制备Li3?2xMgxV2(PO4)3/C (x=0、0.01、0.03、0.05)复合材料，并通过X射线衍射(XRD)、扫描电镜(SEM)和电化学测试等测试手段对合成材料进行表征。XRD 结果表明：在 Li3V2(PO4)3的锂位掺杂少量Mg2+，并没有明显改变Li3V2(PO4)3晶体的单斜结构，但镁掺杂Li3V2(PO4)3的晶胞体积大于未掺杂Li3V2(PO4)3的晶胞体积。所有镁掺杂复合材料Li3?2xMgxV2(PO4)3/C (x=0.01、0.03、0.05)的电化学性能均优于Li3V2(PO4)3/C复合材料，其中，Li2.94Mg0.03V2(PO4)3/C 在上述所有材料中具有最高的容量和最好的循环性能。对 Li3V2(PO4)3/C 和Li2.94Mg0.03V2(PO4)3/C的锂离子扩散系数及电化学性能进行对比分析，结果表明：Li+在镁掺杂Li3V2(PO4)3材料中的快速扩散是由Mg2+在锂位的掺杂造成，Li+在活性材料中的快速扩散使镁掺杂Li3V2(PO4)3材料具有优良的电化学性能。
채용용효?응효법제비Li3?2xMgxV2(PO4)3/C (x=0、0.01、0.03、0.05)복합재료，병통과X사선연사(XRD)、소묘전경(SEM)화전화학측시등측시수단대합성재료진행표정。XRD 결과표명：재 Li3V2(PO4)3적리위참잡소량Mg2+，병몰유명현개변Li3V2(PO4)3정체적단사결구，단미참잡Li3V2(PO4)3적정포체적대우미참잡Li3V2(PO4)3적정포체적。소유미참잡복합재료Li3?2xMgxV2(PO4)3/C (x=0.01、0.03、0.05)적전화학성능균우우Li3V2(PO4)3/C복합재료，기중，Li2.94Mg0.03V2(PO4)3/C 재상술소유재료중구유최고적용량화최호적순배성능。대 Li3V2(PO4)3/C 화Li2.94Mg0.03V2(PO4)3/C적리리자확산계수급전화학성능진행대비분석，결과표명：Li+재미참잡Li3V2(PO4)3재료중적쾌속확산시유Mg2+재리위적참잡조성，Li+재활성재료중적쾌속확산사미참잡Li3V2(PO4)3재료구유우량적전화학성능。
The Li3?2xMgxV2(PO4)3/C (x=0, 0.01, 0.03 and 0.05) composites were prepared by a sol?gel method and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and electrochemical measurements. The XRD results reveal that a small amount of Mg2+ doping into Li sites does not significantly change the monoclinic structure of Li3V2(PO4)3, but Mg-doped Li3V2(PO4)3 has larger cell volume than the pristine Li3V2(PO4)3. All Mg-doped composites display better electrochemical performance than the pristine one, and Li2.94Mg0.03V2(PO4)3/C composite exhibits the highest capacity and the best cycle performance among all above-mentioned composites. The analysis of Li+ diffusion coefficients in Li3V2(PO4)3/C and Li2.94Mg0.03V2(PO4)3/C indicates that rapid Li+ diffusion results from the doping of Mg2+ and the rapid Li+ diffusion is responsible for the better electrochemical performance of Mg-doped Li3V2(PO4)3/C composite cathode materials.