Abstract
The global energy transformation towards electrification and decarbonization urgently requires a sustainable lithium supply. However, current solvent extraction technology suffers from extractant dissolution and low efficiency. Herein, we develop an oil-in-water (O/W) Pickering emulsion with high stability using amphipathic SiO(2) nanoparticles to confine tributyl phosphate (TBP) extractant within the oil phase for enhancing lithium extraction from salt-lake brine. Resultantly, the Pickering emulsion achieves a lithium recovery of 91.7% with Li-Mg separation factor (β(Li)(Mg)) of 101.9 after only three-stage extraction and Li(+) mass transfer rate (k) of 4.57 × 10(-8 )m/s, greatly outperforming the traditional TBP system (52.8% recovery, β(Li)(Mg) = 12, k = 7.50 × 10(-9 )m/s). We propose that the tiny gaps between SiO(2) particles serve as Li(+) transport channels, in which the interfacial electric field generated by surface charges of SiO(2) particles and the confinement effect within these gaps synergistically enhance Li(+) dehydration and diffusion.