尖晶石相型LiM0.2Mn1.8O4（M=Mg、Cd）相的晶格畸变与红外吸收峰频移

Lattice Distortion and FTIR Frequency Shift of Element Doped Spinel LiM0.2Mn1.8O4（M =Mg、Cd）

通过室温固相法制备了不同元素掺杂的前驱体，并采用分步煅烧法获得了尖晶石型LiMn204和LiM0．2Mn1.8O4（M=Mg、Cd）相。采用XRD和F11R技术就元素掺杂对产物晶格畸变、Mn-0键长和键能强度等微观结构参数和光谱频移现象进行分析。结果表明，不同元素掺杂导致产物产生不同程度的晶格畸变。Mg元素掺杂使晶格收缩，Mn（Ⅳ）-0和Mn（Ⅲ）-O键收缩和键能强度增加，对应吸收峰发生蓝移；Cd元素掺杂使晶格膨胀，Mn（IV）-O和Mn（Ⅲ）-O键增长和键能强度降低，对应吸收峰发生红移。

The precursors of the spinel lithium manganates were synthe- sized by solid method at ambient temperature, LiMn2O4 and Mg, Cd ele- ment doped LiM0.2Mn1.8O4 were obtained by two steps calcinations. XRD and FTIR analysis results showed that the two doping elements induced different lattice distortions of LiM0.2Mn~ 804. Mg element doping resulted in the increasing of Mn （ IV ）--O and Mn （III ）--O bond energy and blue shifting of the absorption peaks because of the lattice shrinkage and Cd ele- ment doping resulted in the bond energy decreasing and the red shifting be- cause of the lattice expansion.