Seawater contains significantly larger quantities of lithium than is found on land, thereby providing an almost unlimited resource of lithium for meeting the rapid growth in demand for lithium batteries....

Electrochemical deposition has emerged as a novel approach to fabricate metal–organic framework (MOF) films. Here, for the first time, an aqueously cathodic deposition (ACD) approach is developed to fabricate ZIF‐8 type of MOF membranes without addition of any supporting electrolyte or modulator. The fabrication process uses 100% water as the sole solvent and a low‐defect density membrane is obtained in only 60 min under room temperature without any pre‐synthesis treatment. The membrane exhibits superior performance in C3H6/C3H8 separation with 182 GPU C3H6 permeance and 142 selectivity, making it sit at the upper bound of permeance versus selectivity graph, outperforming majority of the published data up to 2019. Notably, this approach uses an extremely low current density (0.13 mA cm−2) operated under an ultrafacile apparatus set‐up, enabling an attractive way for environmentally friendly, energy efficient, and easily scalable MOF membrane fabrications. This work demonstrates a great potential of aqueously electrochemical deposition of MOF membrane in the future research.

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Zeolitic imidazolate framework 8 (ZIF-8) is effective for C 3 H 6 /C 3 H 8 separation because of the “sieving effect” of a six-membered (6-M) window. Here, we demonstrate that ZIF-8 is a versatile material that could effectively separate C 2 H 4 from C 2 H 6 via its 4-M window along the <100> direction. We established a facile and environmentally friendly carbon nanotube (CNT)–induced oriented membrane (CNT-OM) approach to fabricate a {100}-oriented ZIF-8 membrane (100-M). In this approach, 2-methyimidazole was anchored onto the CNT surface followed by 3-hour in situ growth in aqueous solution at room temperature. The obtained 100-M, whose 4-M window is aligned along the transport pathway, showed ~3 times higher C 2 H 4 /C 2 H 6 selectivity than a randomly oriented membrane. Thus, this work demonstrates that the membrane orientation plays an important role in tuning selectivity toward different gas pairs. Furthermore, 100-M exhibited excellent mechanical stability that could sustain the separation performance after bending at a curvature of ~109 m −1 .

In article number 1907089, Zhiping Lai and co‐workers develop an aqueous cathodic deposition method to fabricate ZIF‐8 membranes. The membrane grows under a current, which provides a self‐healing mechanism, leading to an ultrathin and defect‐free membrane that shows excellent performance in propylene/propane separation.