Efficient uptake of iodine by conjugated microporous polymer@electrostatically spun silk-based composite membranes

• Conjugated microporous polymer composite membranes were successfully prepared by combining electrospinning technology with cross-coupling reaction. • Taking advantage of the flexible design of the molecular structure of the conjugated microporous polymer, amino and imino groups containing electronrich functional groups were strategically added, and the adsorption capacity of iodine was significantly improved through electrostatic interaction , and the adsorption efficiency was as high as 160 %−240 %. • Using the superhydrophobicity of conjugated microporous polymer composite membrane, the adsorption efficiency of iodine is also high in high humidity environment. • The film can still maintain good stability and mechanical properties under complex environmental conditions such as acid, alkali and organic solvent . The release of radioactive iodine from the nuclear industry has caused significant environmental damage, posing serious threats to human health and sustainable development. Existing iodine removal methods face challenges such as low efficiency, poor stability, and limited applicability in harsh environments. To overcome these limitations, in this study, we used electrospun polyurethane (PU) membranes as the support matrix and selected different monomers to synthesize two novel conjugated microporous polymer (CMPs) composite membranes for iodine adsorption via palladium-catalyzed Sonogashira-Hagihara coupling reactions. The resulting CMPs@PU composite membranes demonstrate exceptional mechanical properties, flexibility, superhydrophobicity, and outstanding stability under extreme conditions, including strong acidic and basic solutions, organic solvents, and high temperatures. At 80 °C, the final iodine adsorption capacities of the two composite membranes, CMPs-1@PU and CMPs-2@PU, reached 1630.75 mg g -1 and 2400.36 mg g -1 , corresponding to iodine uptake rates of 163 % and 240 %, respectively. In humid environments, the superhydrophobicity of the membranes significantly mitigated the influence of water on iodine adsorption, with only a <10 % reduction in adsorption efficiency. These two CMPs@PU composite membranes removed iodine from 20 mL l -1 of iodine cyclohexane solution with filtration efficiencies of 99.9 % and 99.7 %. These findings suggest that CMPs@PU composite membranes serve as efficient, stable, and multifunctional iodine removal adsorbents, offering a promising solution for environmental remediation in nuclear waste management and other industrial applications. • Strategy: Integration of electrostatic spinning and cross-coupling for advanced material preparation. • Highlight: Novel superhydrophobic conjugated microporous polymer composite membrane. • Key Features: • Exceptional Adsorption: Superior efficiency for radioactive iodine (160 %-240 %). • Durable Mechanical Properties: Maintains stability and integrity in complex environments. • Significance: Advances research in conjugated microporous polymers and applications in environmental purification and waste disposal.