Electrospun cellulose acetate nanofibers for CO₂ adsorption: the role of zeolite-polymer interactions

The urgent demand for efficient carbon capture technologies has sparked the search for simple, scalable materials with tailored sorption properties. In this study, we demonstrate that unmodified cellulose acetate (CA) nanofiber membranes can serve as effective CO2 sorbents at room temperature, offering a low-cost and environmentally friendly alternative to chemically modified polymeric systems. The distinct wrinkled morphology of the CA nanofibers achieved through targeted electrospinning conditions (solvent selection and high humidity) enhances the surface area and contributes to a CO2 sorption capacity of up to 2.14 mmol/g, comparable to that of more complex porous materials. Beyond single-material systems, we emphasize the often-overlooked role of matrix–additive compatibility in composite membranes. Using a CA/β-zeolite system as a case study, we show that specific interactions between the polymer matrix and active phase–β- ammonium zeolite can entirely suppress CO2 sorption instead of the assumed synergy of sorption properties for both components. The cellulose-based support was chosen for its biodegradability and biocompatibility, further supporting its use in sustainable technologies. To address the stability of modifying agents, we introduce a sandwich-type nanofiber membrane architecture (CA/Zeolite/CA) in which active nanocrystals–β-zeolites are embedded and fixed within layered structures. However, the sandwich structure of the membrane in this case indicated a negative effect of the mutual interaction of the CA carrier and β-ammonium zeolites on the sorption capacity of the composite membrane. Overall, the combination of simplicity, performance, and green chemistry makes CA nanofiber membranes a promising candidate for scalable and sustainable CO2 capture.