Self-driven lithium extraction by directional liquid transport nonwoven

Lithium extraction from seawater/brine has attracted increasing attention because of its abundant reserves. However, most extraction technologies require extra energy consumption to enrich lithium in the solution. Here, we develop a self-driven lithium extraction method by a composite asymmetric nonwoven (CAN) with directional liquid transport functionality. CAN consists of one hydrophobic fibrous layer containing Li-ion sieve particles and one hydrophilic fibrous layer. As a result, a solution containing various types of ions can spontaneously transport through CAN from the hydrophobic to the hydrophilic layer, absorbing Li ions in the hydrophobic layer. CAN exhibits high Li + selective adsorption capacity, good chemical stability, easy recyclability, and long service life. Importantly, extremely low energy of ∼1.631 J is consumed on extracting 1 mg lithium ion by our method using CAN. This work opens a great promise of saving huge energy costs on lithium extraction from seawater or salt lakes.