High Efficient Li + and Cs + Immobilization from Low Concentration Solution by Reversible Intercalation and Deintercalation in GaAs/WO 3 Electrode

The highly efficient enrichment of Li + and Cs + from their low-concentration aqueous solutions is a crucial step for Lithium and Cesium clean production, as well as radioactive Cs + safety remediation from water. The current adsorption and precipitation routes are high energy cost and environmental unfriendly. Electrochemical ion exchange route may serve as a promising alternative route. This study presents results of high efficient, multicycle Li + and Cs + enrichment from their low concentration solutions via intercalation and deintercalation in WO 3 /GaAs composite electrode with Faraday efficiency above 99% and high intercalation capacities 7.25 mg/g for Li + and 38.89 mg/g for Cs +, respectively. After six cycles, 95 and 90% capacities for Li + and Cs + still remained. Both enrichment efficiency and stability are higher than those of LiFePO 4 (LFP) and LiMn 2 O 4 (LMO) under the same conditions. This route might provide a way for low-energy cost and highly efficient Li + and Cs + recovery from contaminated water.