Preparation of a novel hollow porous LiMn2O4 film electrode (H-LMOE) and its improved performance for lithium extraction.

Lithium extraction from the solution in low Li⁺ concentration by an energy-saving and high-efficiency method is still a challenge. Herein, a novel hollow porous LiMn 2 O 4 (H-LMO) with highly active site was proposed to enhance the extraction performance of Li⁺. Based on the established hollow porous structure, the H-LMO film electrode (H-LMOE) exhibits excellent lithium electrosorption performance and stability. Under the current density of 0.5 C, the electrosorption capacity of Li⁺ could reach 31.52 mg/g, the separation coefficient of Li⁺/Mg²⁺ was 581.67, and the energy consumption was as low as 0.49 Wh/mol Li. This unique structural strengthening mechanism made H-LMOE maintain a good Li⁺ extraction performance even in a solution of low Li⁺ concentration. The Li⁺ electrosorption capacity of H-LMOE was 2.13 times that of T-LMOE in a 60 mg/L Li⁺ solution, while the specific energy consumption of the H-LMOE was 15.78% lower than that of the traditional-LiMn 2 O 4 film electrode (T-LMOE). Even in a 10 mg/L Li⁺ solution, the electrosorption capacity of H-LMOE was 21.48 mg/g, which was 10.0% higher than that of T-LMOE. Moreover, after 50 recycling processes, the final electrosorption capacity of the H-LMOE was about 25.0% higher than that of the T-LMOE. • We supplemented the XPS of H-LMO electrode after 50 cycles of Li⁺ adsorption. • We supplemented the discussion about the difference between electro-adsorption and chemical adsorption in Introduction. • We supplemented and corrected the data and formatting errors in the manuscript. [ABSTRACT FROM AUTHOR]