Design, preparation and characterization of silica-integrated polymeric networks incorporating cobalt-ferrite spinel nanoparticles by freeze-drying method: a novel hybrid material

Official URL: https://dx.doi.org/10.1016/j.mtcomm.2025.114209

In this study, a novel silica (Si)-integrated polymeric network incorporating CoFe₂O₄ nanoparticles was designed as a aerogel structure and synthesized via a freeze-drying method. The polymeric network was composed of water-soluble biopolymer derivatives, including carboxymethyl cellulose (CMC), hydroxyethyl cellulose (HEC), and xanthan gum (XG), which provide structural versatility and enhance the stability of the hybrid system. Moreover, to improve the dispersion and electrostatic stability of CoFe₂O₄ nanoparticles within Si matrix, stable water-based suspensions were prepared using SDS and APTES as two different surface modifiers. Hence, the sulfate and amine functional groups in the modified CoFe2O4 suspensions strongly promoted crosslinking within the polymeric matrix through synergistic electrostatic interactions, hydrogen and covalent linkages. Besides, freeze-drying facilitated the formation of a highly porous and biocompatible aerogel structure while preserving the key properties of the polymeric network. The structural, morphological and thermal properties of the synthesized hybrid polymeric aerogels were investigated by optical microscopy, SEM, FT-IR, XRD, and TGA. The thermal stability of Si-based aerogels, with CoFe-APTES in Si-CMC showed the highest remaining substance at 1000°C (65.4 %). The physicochemical properties of the Si-based hydrogels revealed that Si-XG exhibited the highest viscosity (7985 mPa·s) and density (1.0452 g/cm3). All pristine and nanoparticle-embedded aerogels exhibited a contact angle of 0°, confirming their strong absorption due to the highly abundant hydroxyl and carboxyl groups. This work presents a novel silica-integrated polymeric network embedded with CoFe₂O₄ nanoparticles, designed to offer multifunctionality and broaden the scope of advanced materials for applications in catalysis, sensing, biomedicine, and flexible electronics.