BO33− lattice engineering regulates the flexibility of Li+ channels in LiFePO4 for Li+ extraction from Salt Lakes at low temperatures

BO 3 3− lattice engineering expands LiFePO 4 channels for faster lithium extraction. • LFP-BO 3 electrodes provide good low-temperature performance. • LFP-BO 3 electrodes exhibit high selectivity in complex brine systems. To mitigate the sluggish lithium extraction kinetics of LiFePO 4 (LFP) constrained by intrinsic ionic channels in high-altitude, low-temperature salt lakes, this study employs a BO 3 3− lattice engineering strategy to induce lattice expansion and flexibilization in LFP by partially substituting PO 4 3− . Characterization confirms uniform BO 3 3− doping and dilated Li + channels. Electrochemical testing reveals that the optimized LFP-2%BO 3 electrode delivers outstanding kinetics, achieves an average lithium extraction of 9.8 mg·g −1 over eight cycles in the West Taijinar raw brine. Retaining 94.2% of its room-temperature Li + extraction capacity in a pure lithium solution at 0 °C, and achieves an average lithium adsorption of 20.21 mg·g −1 at −20 °C, which is more than twice that of the unmodified electrode. Furthermore, it enhances Li + selectivity while effectively suppressing the co-intercalation of Na + and Mg 2+ . The mechanism entails BO 3 3− widening channels and constructing robust transport networks to accelerate low-temperature ion migration. This study provides novel materials and theoretical insights for efficient lithium extraction from high-altitude, low-temperature salt lakes. Download: Download high-res image (236KB) Download: Download full-size image