Stabilize the oxygen vacancies in CuFe2O4 via altering local electronic structure by Co doping: Critical role of Co doping and photo-Fenton degradation of chloramphenicol

Abstract

Background

The indiscriminate use of chloramphenicol (CHLORO) leads to its release into surface and groundwaters which causes the emergence of antibiotic-resistant bacteria that could pose a detrimental threat to human health and aquatic life.

Methods

Herein, we investigated the manipulation of lattice strain in CuFe₂O₄ (CFO) through cobalt (Co) doping and oxygen vacancies (O_V) by a simple co-precipitation method for improved photocatalytic performance. The critical role of Co doping and photo-Fenton degradation of chloramphenicol CHLORO under visible light irradiation was investigated.

Findings

The study highlighted the enhanced photocatalytic degradation of CHLORO by Cu0_.6Co_0.4Fe₂O₄ nanocatalyst (Co-CFO-0.4 NCs) and it reached 99.8 % and the photocatalyst was stable even after 6th cycle. Here, the analysis of the CFO material indicates that Co doping creates unique compressive forces, whereas O_V leads to tensile forces, both contributing to the enhancement of localized lattice strain. The Co-CFO-0.4 NCs exhibited 1.51 times enhanced photocatalytic activity than pristine compounds for CHLORO degradation. The predominant generation of hydroxyl radical (•OH) by Co-CFO-0.4 NCs along with contributions from hydrogen peroxide (H₂O₂), significantly increases the catalytic activity of the material, leading to complete degradation of CHLORO. The radical's formation was validated by using electron spin resonance (ESR) and scavenging studies. Additionally, the degradation pathway of CHLORO by Co-CFO-0.4 NCs were proposed and the possible toxicity associated with the intermediated were predicted. The study underscores the importance of engineering O_v and surface doping to enhance the performance of photocatalysts, thereby contributing to wastewater remediation.