为了得到LiMn2O4在空气中的分解动力学,用TG、XRD和H-E积分方程研究其分 解过程.1070-1210K的分解反应为LiMn2O4(Cubic)→LiMn2O4-δ(Orthorhombic)+δ／2O2, 过程属于成核生长控制,活化能为204.16kJ／mol.1210-1473K的分解反应为3LiMn2O4-δ (Orthorhombic)→LiMnO2+Mn3O4+Li2Mn2O4+(1-3δ／2)O2,1210-1300K内的分解过程属于 成核生长控制,活化能为185.61kJ／mol,在1300-1473K内的分解过程属扩散控制,活化能为 208.74kJ／mol.由H-E积分方程得到的动力学参数InA与E、logC与m间存在明显的动力 学补偿效应.
In order to get the decomposition kinetics of LiMn2O4 in air, its decomposition process was studied with TG, XRD and H-E integrated equation. The decomposition reaction from 1070K to 1210K is
LiMn2O4 (Cubic)→LiMn2O4-δ(Orthorhombic) +δ/2O2(g)↑, which is controlled by nucleating and growing, and the activated energy is 204.16kJ/mol. The reaction from
1210K to 1473K is 3LiMn2O4-δ(Orthorhombic)→LiMnO2+ Mn3O4 +Li2Mn2O4+(1-3δ/2)O2 (g)↑. Nucleating and growing is the key step of
the process from 1210K to 1300K, and its activated energy is 185.61kJ/mol. But the process from 1300K to 1473K is controlled by diffusion, and its activated energy is 208.74kJ/mol. The kinetical compensative effects not
only exist in Arrhenius equation but also in Harcourt-Esson equation.
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