A multifunctional Co-doped BiFeO3 nanocomposite: a promising candidate for photocatalytic degradation, antibacterial activity, and antioxidant applications

Abstract

This study investigates the synthesis and multifunctional applications of a cobalt-doped bismuth ferrite (Co@BFO) nanocomposite, emphasizing its efficacy in photocatalytic degradation of malachite green (MG) dye, antibacterial activity against foodborne pathogens, and antioxidant capacity. The Co@BFO nanocomposite was synthesized via a hydrothermal method, exhibiting a crystallite size of approximately 30 nm and a surface area of 16.2 m² g⁻¹. Under sunlight irradiation, the nanocomposite achieved a remarkable 97% degradation of MG dye at a concentration of 15 mg L⁻¹ within 120 minutes. The degradation kinetics followed a pseudo-first-order model with a rate constant of 0.0289 min⁻¹. The Co@BFO nanocomposite demonstrated significant antibacterial effects against Klebsiella pneumoniae and Bacillus cereus, achieving an MIC of 10 μg mL⁻¹. Additionally, it exhibited a DPPH radical scavenging activity ranging from 14.8% to 84.8% at concentrations between 2.5 to 15 mg L⁻¹, with an IC₅₀ value of 11.13 mg L⁻¹. These results confirm that the Co@BFO nanocomposite not only effectively degrades organic pollutants, but also serves as a potent antimicrobial and antioxidant agent. This multifunctionality suggests its potential for diverse applications in environmental remediation and public health.