Nanoarchitectured composite of polysulfone and carbon-based fillers bearing magnetically stimulable function for efficient CO2 capture

Abstract

Mitigating the global warming caused by CO₂ emissions from anthropogenic sources is a hot research topic in the current era. The high cost and difficulty in handling liquid solvent absorbents for CO₂ capture are the main barriers to their industrial application. Earth-abundant solid sorbents are favorable candidates for CO₂ separation, offering a low energy penalty for CO₂ desorption. Here, Polysulfone (PSF) nanocomposites were prepared by simple solution blending. The carbon-based fillers, namely carbon nanotubes (CNT), and activated carbon (CA) in the range of 5–20 wt%, containing iron nanoparticles, were used as fillers. Their morphological, thermal, CO₂ capture capacity and magnetic properties were comprehensively studied. Transmission electron microscopy (TEM) evidenced uniform filler distribution in the polymer matrix with sizes of 47–54 nm. Thermal analysis revealed an approximately 4 °C improvement in both the initial (T_onset) and maximum (T_max) degradation temperatures by adding 5 wt% of nanoparticles compared to the pristine polymer. The glass transition temperature (T_g) of the pristine PSF and produced nanocomposites showed identical values as estimated by differential scanning calorimetry (DSC). The increase in filler amount gradually decreased the water contact angle values, indicating a hydrophilic classification of the PSF nanocomposites. The obtained PSF nanocomposites exhibited an efficient CO₂ capture capacity of about 40–61 mgCO₂/g at 45 °C, higher than pristine PSF. This remarkable achievement sets a new benchmark compared to previously developed systems. The introduction of the filler transforms the diamagnetic polymer matrix into a ferromagnet, presenting a coercivity of about 480 Oe, enhancing the material's potential for applications in microelectronics.