Preparation and performance study of a BaTiO3-LiFePO4 piezoelectric composite-based lithium-ion sieve for lithium extraction from salt lake brines under natural conditions

Lithium is widely used in digital products and new energy vehicles due to its low density and low redox potential, and there are huge prospects for extracting lithium from the brines of salt lakes. In addition, it is well known that the majority of the lithium salt lake brines on Earth have been identified in high-altitude areas with harsh geographical environments. Nevertheless, there are also rich natural energy sources, such as wind and tidal energy. Therefore, it is vital to develop a novel variety of lithium-ion sieves that can utilize natural energy. It is highly exclusive and selective for lithium-ions in salt lakes to achieve low-cost and large-scale lithium extraction under natural conditions. In this paper, BaTiO 3 -LiFePO 4 (BTO-LFP) piezoelectric composite-based lithium-ion sieve materials were successfully prepared and utilized to convert kinetic energy into electrical energy, which should be used in lithium extraction from raw brines with natural energy. According to the experiments, the materials can reach adsorbing equilibrium in simulated brine after 48 h. The lithium adsorption amount is 21.5 mg/g and can also reach adsorbing equilibrium in Yi-Liping raw salt lake brines after 72 h, and the adsorption amount can also reach 21.7 mg/g which indicates that this lithium-ion sieve is specific and selective for lithium-ion. What's more surprising is that this lithium-ion sieve only uses natural kinetic energy as the driving force for lithium extraction. Therefore, this study has devised an innovative technique for extracting lithium from natural brines, which shows significant promise, for the large-scale exploration of lithium resources from salt lakes under harsh natural conditions.