Department of Chemistry and Sungkyun Advanced Institute of NanoTechnology (SAINT), Sungkyunkwan University, 2066, Seobu-ro, Jangan-gu, Suwon, Gyeonggi-do, 16419, Korea.
Chem Asian J. 2021 Apr 19;16(8):974-980. doi: 10.1002/asia.202100126. Epub 2021 Mar 18.
Silicon oxide-coated lithium aluminum layered double hydroxide (Li Al -LDH@SiO ) nanocrystals (NCs) are investigated to selectively separate lithium cations in aqueous lithium resources. We directly synthesized Li Al -LDH NC arrays by oxidation of aluminum foil substrate under a urea and lithium solution. Various lithium salts, including Cl , CO , NO , and SO , were applied in aqueous solution to confirm the anion effect on the captured and released lithium quantity of the Li Al -LDH NCs. In a 5% solution of sulfate ions mix with lithium chloride, the Li Al -LDH NCs separated a larger quantity of lithium than in other anion conditions. To enhance regeneration stability and lithium selectivity, thin layers of SiO were coated onto the Li Al -LDH nanostructure arrays for inhibition of nanostructure destruction after desorption of lithium cations in hot water. The Li Al -LDH@SiO nanostructures showed enhanced properties for lithium adsorption, including increase of stable regeneration cycles from three to five cycles, and they showed high lithium selectivity in the Mg , Na , and K cation mixed aqueous resource. Our nanostructured LDH lithium adsorbents would provide a facile and efficient application for cost-efficient and large-scale lithium production.
氧化硅包覆的锂铝层状双氢氧化物（LiAl-LDH@SiO）纳米晶体（NCs）被用于选择性地从含锂水溶液中分离锂离子。我们通过在尿素和锂溶液存在的条件下氧化铝箔衬底直接合成了 LiAl-LDH NC 阵列。在水溶液中应用了各种锂盐，包括 Cl-、CO32-、NO3-和 SO42-，以确认阴离子对 LiAl-LDH NC 捕获和释放锂离子数量的影响。在 5%的硫酸盐离子和氯化锂混合溶液中，LiAl-LDH NCs 分离出的锂离子数量比其他阴离子条件下更多。为了提高再生稳定性和锂的选择性，将薄的氧化硅层涂覆在 LiAl-LDH 纳米结构阵列上，以抑制在热水中脱附锂离子后纳米结构的破坏。LiAl-LDH@SiO 纳米结构在锂离子吸附方面表现出增强的性能，包括从三个稳定再生循环增加到五个循环，并且在 Mg、Na 和 K 阳离子混合水溶液资源中表现出高的锂选择性。我们的纳米结构 LDH 锂吸附剂将为高效且经济的大规模锂生产提供一种简便且有效的应用。
