Work

Role of cobalt incorporation in the photo-Fenton activity of magnetite under natural solar irradiation

Year: 2026

Type: article

Abstract: Magnetite based catalysts have been extensively studied for the decomposition of hydrogen peroxide for generation of hydroxyl radicals (HO • ) through Fenton reaction aiming environmental applications. A series of cobalt containing magnetite (Co x Fe 1-x )Fe 2 O 4 , with x = 0, 0.25, 0.50, 0.75, and 1) was synthesized and correlated to photo-Fenton process efficiency under natural solar irradiation under near neutral conditions. The magnetites were characterized by X-ray diffraction (XRD), specific surface area, scanning electron microscopy (SEM), zeta potential (ZP) and X-ray photoelectron spectroscopy (XPS). The cobalt incorporation on magnetite structure enhanced by two times the catalytic activity regarding H 2 O 2 decomposition (k = 3.98 × 10 −03 min −1 for (Co 0.25 Fe 0.75 ) Fe 2 O 4 against 2.06 × 10 −03 min −1 for Fe 3 O 4 ). (Co 0.25 Fe 0.75 )Fe 2 O 4 completely degraded trimethoprim (TMP) and sulfamethoxazole (SMX) after 170 kJ m −2 (∼90 min), achieving concentration below the limit of detection at pH 5.5, without metal leaching, ensuring a heterogeneous process. The catalyst demonstrated stability over four reuse cycles and high performance in an effluent from a local Wastewater Treatment Plant (WWTP), with 85% and 76% degradation of TMP and SMX, respectively. These findings highlight the viability of its use under natural solar irradiation for the treatment of WWTP effluents at circumneutral conditions and recyclability, overcoming the main limitations of conventional Fenton systems.

Source: Materials Science and Engineering B

DOI: 10.1016/j.mseb.2026.119432

Authors: Jany H.F. de Jesus, Karla V.L. Lima, David L.A. da Silva, Raquel F. Pupo Nogueira

Institutions: Universidade de São Paulo, Universidade Estadual Paulista (Unesp)

Language: English

Topic: Advanced oxidation water treatment

Subfield: Water Science and Technology

Field: Environmental Science

Domain: Physical Sciences

SDGs: Clean water and sanitation, Responsible consumption and production

Open Access status: hybrid

Estimated APC paid: $3,140