Improved dye adsorption and photodegradation using mesoporous carbon modified with titania and magnetic nanoparticles

This study investigated the adsorption and photocatalytic potential of methylene blue (MB) and indigo carmine (IC), cationic and anionic dyes, respectively, exploring the unique properties of carbon xerogel modified with titanium oxide and Fe 2 O 3 (Fe/CX-Ti). To achieve a detailed characterization of the structural, chemical, and surface properties of the Fe/CX-Ti composite, various analytical techniques were employed, including powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), potentiometric titration, N 2 sorption isotherms, scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS). The evaluation of Fe/CX-Ti as an adsorbent for dyes revealed an optimal pH of 11.0 for methylene blue and 3.0 for indigo carmine, indicating its enhanced adsorption capacity. The maximum adsorption capacity, determined by the Langmuir model, reached 784.3 mg.g −1 for MB and 448.9 mg.g −1 for IC. Additionally, the Fe/CX-Ti composite exhibited excellent efficiency in the photocatalytic degradation of the dyes, achieving 100% degradation of methylene blue and 98% of indigo carmine in just 90 min. Notably, Fe/CX-Ti demonstrated typical catalytic activity and ferromagnetic properties, enabling easy separation of the material from the solution and allowing its reuse in multiple cycles. • Fe/CX-Ti nanocomposites exhibited high dye degradation activity. • Fe/CX-Ti composite as adsorbent showed selectivity for different dyes at different pHs. • Fe/CX-Ti composite holds promise for dye removal applications in aqueous solutions, providing a blend of efficiency for environmental remediation processes. • The Fe/CX-Ti magnetic, adsorptive, and photocatalytic properties, demonstrated high efficacy in dye adsorption and degradation.