Characterization and Deployment of Surface-Engineered Cobalt Ferrite Nanospheres as Photocatalyst for Highly Efficient Remediation of Alizarin Red S Dye from Aqueous Solution

Abstract

Hazardous effluents in the wastewaters deteriorate the ecosystem and its effective treatment is of interest to the scientific community. In this context, herein, the cobalt ferrite (CoFe2O4) nanospheres were fabricated and inspected for photo-catalytic-driven degradation of a hazardous Alizarin Red S (ARS) dye, as a model pollutant. For effective preparation of CoFe2O4 nanospheres, triethylene glycol (PEG) was used as a stabilizing agent, during the reaction of cobalt oxide and iron sulfate, followed by thermally annealed and etched with 1 M hydrochloric acid. The surface of annealed nanospheres was functionalized by using 3-(triethoxysilyl)propylamine (APTES). The as-prepared pristine, annealed, and surface functionalized CoFe2O4 nanospheres were characterized by analytical techniques, such as Fourier transform infrared (FTIR), X-ray diffraction (XRD), and scanning electron microscopy (SEM). From the XRD profile, the particle size of annealed and functionalized nanospheres were 17.3 and 21 nm, respectively. FTIR study corroborates the surface tailoring of CoFe2O4 nanospheres. The SEM analysis of F-CoFe2O4 nanospheres showed that the bigger aggregates of nanospheres disappear, and the overall distribution of particles was notably improved after functionalization. The surface engineered nanospheres presented high efficiency for ARS dye degradation under the optimal conditions of irradiation time, pH, adsorbent dose, dye dose, and different acids. Kinetics models explained that the degradation reaction following pseudo-first-order kinetics. The turnover number (TON) reached up to 2.75 × 108, 2.85 × 108 and 3.01 × 108 for bare, annealed and functionalized CoFe2O2 nanoparticles, respectively. In conclusion, the results indicate a high potential of photo-driven catalytic remediation of tested hazardous dye by engineered cobalt ferrite nanospheres and encourage further work on photocatalytic abatement of organic contaminants.