PVA-enhanced green synthesis of CMC-based lithium adsorption films

The titanium-based lithium ion sieve (HTO), renowned for its exceptional adsorption performance and cyclic stability, was utilized in addressing the global shortage of lithium resources. However, the recovery and reuse efficiency of HTO in powder form is relatively low, which limits its application in industrial fields. To address this issue, this study utilized carboxymethyl cellulose (CMC) as the principal matrix material, while polyvinyl alcohol (PVA) played a dual function as both matrix and crosslinker, negating the necessity for supplementary crosslinking materials. Employing water as the only solvent, HTO was embedded into the CMC-PVA blended film matrix. It was observed that augmenting the CMC content substantially elevates the adsorptive capability of the film. However, this enhancement comes at the cost of reduced mechanical robustness and diminished stability in solution. Consequently, by balancing the influence of adsorptive capacity and stability through fine-tuning the CMC-to-PVA ratio. Even when HTO powder is encapsulated within the film, the adsorption film retains the excellent adsorption properties of HTO, achieving an adsorption capacity for lithium of 29.21 mg g⁻¹ within 12 h. This study provides an innovative pathway and ideas for the large-scale, low-cost production of sustainable lithium-ion adsorption materials.