Construction of robust H2TiO3@PAM hydrogel ion-sieve via in-situ polymerization for Li+ adsorption

The lithium-ion sieve primarily exists in powder form, which poses challenges such as poor fluidity and permeability, as well as difficulties in recovery. The H₂TiO₃ (HTO) particles were introduced into polyacrylamide (PAM) via in situ polymerization to prepare a tough and porous nanocomposite hydrogel (HTO@PAM). This method effectively addresses the recovery difficulties associated with powdered lithium-ion sieves and, due to the hydrophilic groups in polyacrylamide, enhances the desorption of Li + and improves the adsorption performance. The results show that HTO@PAM-4 is the optimal ratio, with an adsorption performance of 32.8 mg/g. Tensile strength tests using a universal testing machine indicated that HTO@PAM-4 has a tensile strength of 0.19 MPa, demonstrating excellent mechanical properties. Infrared spectroscopy detected the presence of hydrophilic groups (-CONH 2 ) in HTO@PAM, and surface tension measurements showed a water contact angle of 8.9 °, indicating good hydrophilicity. The recyclability of HTO@PAM-4 was investigated, and after six cycles, the adsorption capacity was 25.4 mg/g, which is 77 % of the maximum adsorption performance, demonstrating recyclability. The results indicate that HTO@PAM exhibits excellent mechanical properties, adsorption performance, and recyclability, making it a material with promising practical applications.