Low-cost and stable Li1.5Al0.3Ti1.7Si0.2P2.8O12 glass–ceramics for lithium extraction from seawater

Rapid development of electronic and grid storage technologies based on lithium-ion batteries are leading to tight supply of lithium resources in the future. Extracting lithium from seawater can completely solve the problem of lithium resource shortage. An electro-deposition method based on a lithium superionic conductive solid-state electrolyte, Li 1.5 Al 0.5 Ge 1.5 (PO 4 ) 3 (LAGP), has been reported to obtain metallic lithium from seawater. However, expensive LAGP increases the cost of lithium extraction, while Li 1.3 Al 0.3 Ti 1.7 (PO 4 ) 3 (LATP) with relatively lower prices cannot meet the stable requirements. Herein, a low-cost, stable glass–ceramics, Li 1.5 Al 0.3 Ti 1.7 Si 0.2 P 2.8 O 12 (LATSP), has been prepared for lithium extraction from seawater. The LATSP glass–ceramics show good selectivity towards Li + and exhibit a high ionic conductivity of 3.98 × 10 −4 S cm −1 at 22 °C. After soaking in simulated seawater, LATSP showed much better stability than LATP, comparable to LAGP. The resultant LATSP glass–ceramics was successfully employed in a seawater lithium extraction device, with a high lithium extraction Coulombic efficiency of 94.0%. Moreover, the LATSP exhibits an ionic conductivity of 2.80 × 10 −4 S cm −1 and maintains a complete structure after 45 h of lithium extraction. This work presents an effective and practical Li-ion conducting membrane for lithium extraction from seawater. Graphical Abstract