Because of its excellent stabilities, polyvinylidene fluoride (PVDF) is commonly employed as a binder in electrode fabrication. However, poor adhesion and hydrophilicity limit its applicability. Herein, PVDF as the hydrophobic framework, polyacrylic acid (PAA), and carboxymethylcellulose lithium (CMCLi) composite binders were cross-linked with phytic acid and Li 1-x Mn 2 O 4 /C were used in the formulation. After 100 electrochemical cycles, the film electrode Li 1-x Mn 2 O 4 /C/PAA- c -CMCLi- b -PVDF exhibits excellent adhesion (0.93 N cm −1 ) and a low capacity fading rate (8.2 %). Furthermore, this film electrode demonstrated a high intercalation capacity (32.14 mg g −1 ), a short intercalation equilibrium time (within 2 h), and a fast Li + intercalation rate, which can be attributed to the synergistic effect of electrolyte permeability enhanced by hydrophilic functional groups (–OH and –COOH), dispersibility of electrode material particles improved by high slurry rheology, and the high transport efficiency of –COOH for Li + . These promising results suggest that this double cross-linked Li 1-x Mn 2 O 4 /C/PAA- c -CMCLi- b -PVDF film electrode is suitable for the selective extraction of Li + .
The rapid growth in lithium demand for battery applications has driven the need for safe and efficient extraction technologies from salt lake brines. Current methods face challenges including low recovery rates, slow adsorption kinetics, and environmental concerns from organic solvent usage. To address these limitations, the environmentally friendly electrochemically switched ion exchange (ESIX) system using a three-dimensional LiMn 2 O 4 /C/SA-c-PEO@GF electrode was developed. The electrode employs sodium alginate (SA) and polyethylene oxide (PEO) as chemically cross-linked binders on a graphite felt (GF) current collector. In the constant current-constant voltage coupling drive mode, the system achieved 97% lithium extraction efficiency with an adsorption capacity of 3.89 mg·g −1 and a Li + /Mg 2+ separation coefficient of 191, the energy consumption was 14.51 Wh·mol −1 and 485 mg·L −1 Li + solution was obtained from actual Zarkhan Salt Lake brine (Mg 2+ /Li + : ∼426.6) by one-step concentration. This study shows the LiMn 2 O 4 /C/SA-c-PEO@GF electrode with high extraction efficiency and fast adsorption rate, providing a simple and efficient method for lithium recovery from salt lake brine with high Mg 2+ /Li + ratio.
危险品化学品经营许可证（带存储）