澳大利亚蒙纳士大学Xiwang Zhang团队制备了能够快速和选择性锂离子传输的定向UiO-67金属-有机框架膜。相关研究成果发表在2021年11月19日出版的《德国应用化学》。

金属有机框架（MOFs）膜具有高的孔密度和可调节的孔径，当设计和制备得当时，其在离子分离方面表现出巨大的潜力。采用冲洗辅助二次生长法，在聚乙烯吡咯烷酮（PVP）修饰的AAO基底上合成了沿[022]方向优先生长的良好共生UiO-67膜。由于UiO-67纳米晶体的定向生长，在整个UiO-67/AAO膜上形成了高度互连的离子传输通道，从而实现了27.01 mol·m^-2·h^-1的超高Li⁺渗透率以及高达159.4的非常好的Li⁺/Mg²⁺选择性。

分子动力学模拟表明，高选择性与Li⁺和Mg²⁺之间传输能垒的巨大差异有关，这是由独特的双峰和定向膜通道中离子脱水程度不同引起的。

附：英文原文

Title: Oriented UiO-67 Metal–Organic Framework Membrane with Fast and Selective Lithium-Ion Transport

Author: Rongming Xu, Yuan Kang, Weiming Zhang, Xiwang Zhang, Bingcai Pan

Issue&Volume: 2021-11-19

Abstract: Metalorganic frameworks (MOFs) membranes with high pore density and tunable pore size down to subnanoscale exhibit great potentials in ion separation when appropriately designed and prepared. By a washing-assisted secondary growing method, a well intergrown UiO-67 membrane with preferential growth along [022] direction is synthesized on polyvinylpyrrolidone (PVP)-modified AAO substrate. Because of the oriented growth of UiO-67 nanocrystals, highly interconnected ion-transporting channels are created throughout the UiO-67/AAO membrane to achieve ultrahigh Li  +  permeance of 27.01 mol·m  2  ·h  1  as well as very decent Li  +  /Mg  2+  selectivity of up to 159.4. Molecular dynamics simulations reveal that the high selectivity is associated with the large disparity of transport energy barrier between Li  +  and Mg  2+  , which is caused by different extent of ion dehydration in unique bimodal and oriented membrane channels.

DOI: 10.1002/anie.202115443

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202115443