Cetyltrimethylammonium Bromide@CoFe2O4 Nanocomposite for Photocatalytic Reduction of Cr(VI) Employing a Simple Colorimetry Assay

The present study involved the synthesis of a nanocomposite material composed of cobalt ferrite (CoFe2O4) modified with cetyltrimethylammonium bromide (CTAB). The preparation method employed a chemical reduction approach. The structural characterization of the CTAB@CoFe2O4 nanocomposite was carried out using techniques such as transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). The XRD analysis confirmed the single-phase cubic crystal structure of the CTAB@CoFe2O4 nanocomposite. Additionally, the FTIR spectra provided evidence of the presence of CTAB functional groups within the CoFe2O4 matrix. The zeta potential measurements revealed a positive surface charge of +17.3 mV for the CTAB@CoFe2O4 nanocomposite. The application of this nanocomposite material was studied for the reduction of chromium (VI) ions (Cr(VI)) from aqueous solutions using a colorimetric method based on 1,5-diphenylcarbazide dye (DPC). The effects of various parameters, including pH, nanocomposite dosage, and contact time, were investigated to assess their influence on the photoreduction efficiency of the CoFe2O4/CTAB nanocomposite. Remarkably, at a nanocomposite dosage of 3 mg/mL, 99% reduction of Cr(VI) was achieved at pH3 with a contact time of 150 minutes. These findings indicate the potential of the synthesized CoFe2O4/CTAB nanocomposite as an efficient material for the elimination of Cr(VI) ions from contaminated water sources. One notable distinction of this method is that it goes beyond solely removing Cr(VI) from water, it also converts it into a non-toxic form.