TY  - JOUR
AU  - Rodrigues, Bianca Gonçalves
AU  - de Faria Braga, Elaine Alves
AU  - Martins, Marccus Victor Almeida
AU  - de Carvalho Oliveira, Jocélia Pereira
PY  - 2026
DA  - 2026/06/07
TI  - Rapid Degradation of Tartrazine Yellow Dye by Photo-Fenton Action at the Interface of Magnetite and Silica Nanoparticles
JO  - Catalysis Research
SP  - 005
VL  - 06
IS  - 02
AB  - This study reports the synthesis of magnetic nanoparticles (Fe3O4) supported on silica (SiO2), obtained from the chemical and thermal treatment of coconut mesocarp. The spectroscopic and morphological properties of this nanocomposite composed of magnetite and silica (Np-Fe3O4/SiO2) were investigated using Infrared (FTIR), Ultraviolet and Visible (UV-Vis), X-ray Diffraction (XDR), Field Emission Scanning Electron Microscopy (FEG-SEM), and Energy Dispersive X-ray Spectroscopy (EDS) techniques. The synthesized material was applied in heterogeneous catalytic reactions to photodegrade the tartrazine yellow dye in the presence of hydrogen peroxide (Fenton reaction). FTIR spectra showed that treatment in a basic medium (NaOH) promotes the rupture of lignocellulosic fiber units, thereby decreasing the intensity of the chemical bonds. Heat treatment at 800°C generates silica, confirmed by the presence of the Si–O–Si band stretching vibration. Morphologically, the generated silica presented a random geometry, with particles larger than 10 µm filled with pores. The magnetite synthesized by basic co-precipitation on the silica presented an average diameter of 10 nm, as confirmed by FEG-SEM images and the Scherrer equation. The photocatalytic performance of the Np-Fe3O4/SiO2 was analyzed, achieving nearly 100% degradation of the tartrazine dye in 75 minutes of reaction in the presence of H2O2. In the absence of H2O2, the dye concentration decreases by only 18% over the same reaction time, probably due to saturation of the dye molecules at the nanocatalyst interface. The adsorption equilibrium parameters were investigated using the Langmuir adsorption isotherm model, which revealed that the adsorption capacity of the Np-Fe3O4/SiO2 system is approximately twice that of the SiO2 system: the maximum amount of dye adsorbed on the nanomaterial’s (qm) surface was 0.35 mg/g for SiO2 and 0.79 mg/g for Fe3O4/SiO2. This photodegradation efficiency is associated with an increase in the nanoparticle’s surface area, which enhances the adsorption capacity for dye molecules. Furthermore, the excess radicals generated by the Fenton reaction also catalyze the degradation of the dye.
SN  - 2771-490X
UR  - https://doi.org/10.21926/cr.2602005
DO  - 10.21926/cr.2602005
ID  - Rodrigues2026
ER  -