采用水热法制备前驱体Li1.6Mn1.6O4,用液相沉淀法在其表面包覆ZrO2,再经酸洗转型为包覆ZrO2的锂离子筛H1.6Mn1.6O4.采用XRD、SEM、EDS和HRTEM对前驱体的结构、形貌和成分进行了表征.研究了ZrO2包覆量和焙烧温度对锰溶损率和锂吸附容量的影响.结果表明:当ZrO2包覆量为3％,焙烧温度为450℃时,在前驱体表面形成厚度约15 nm的ZrO2包覆层,首次锰溶损率从3.14％下降到2.65％,锂离子筛在盐湖卤水中锂吸附容量保持为29.4 mg·g-1.包覆ZrO2的锂离子筛经过10次循环吸附-脱附,锰溶损率降低至0.34％,锂吸附容量保持为24.4 mg·g-1,高于未包覆的锂离子筛(22.9 mg· g-1).包覆ZrO2改善了锂离子筛的结构和吸附容量的循环稳定性.%ZrO2-coated H1.6Mn1.6O4 was synthesized from Li1.6Mn1.6O4 precursor prepared by a hydrothermal method.The liquid precipitation process followed by acid washing was utilized to coat ZrO2 on the precursor.The structure,morphology and composition of the ZrO2-coated precursor were investigated by SEM,XRD,EDS and HRTEM analysis.The influences of coating content and roasting temperature on Mn dissolution loss ratio and Li adsorption capacity were discussed.The results indicate that a layer of ZrO2 with 15 nm in thickness is coated on the precursor when ZrO2 content is 3％ and roasting temperature is 450 ℃.The Mn dissolution loss ratio decreases from 3.14％ to 2.65％ and Li adsorption capacity of the resulting ion sieve in the salt lake brine maintains 29.4 mg·g-1.After 10 cycles of adsorption and desorption,the corresponding Mn dissolution loss ratio and Li adsorption capacity is 0.34％ and 24.4 mg ·g-1,respectively.The adsorption capacity is higher than the bare lithium ion-sieve (22.9 mg·g-1).The results suggest that the structure and cycle stability of H1.6Mn1.6O4 are improved by a ZrO2 coating layer.
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