Peroxidase like activity of Prussian blue nanoparticles and visible light mediated catalytic degradation of methylene blue dye

The environmental impact of dyes, particularly those utilized in the pharmaceutical and textile industries, has been a growing concern due to their persistence and potential harm to ecosystems. Methylene Blue (MB) dye is one of the commonly used synthetic dyes known for its adverse effects on the environment. Thus a promising catalyst is required for the effective degradation of MB dye. To effectively degrade MB, we have synthesized Prussian blue nanoparticles (PBNPs) in this work using the co-precipitation technique. These nanoparticles showed the peroxidase like behavior by degrading hydrogen peroxide and generating ROS (reactive oxygen species) under visible light exposure, which oxidized MB leads to its degradation. This degradation process was investigated under various experimental conditions, including pH, catalyst dosage, and peroxide concentration. The results demonstrated that PBNPs exhibited remarkable catalytic activity and completely degrade the MB within 50 min under visible light. The degradation efficiency was found to be pH-dependent and optimum efficiency was found in pH range from 5 to 7. The kinetic studies were shown that this MB degradation process follows the first order kinetic models with the rate constant value 0.038 s − 1, suggesting that the degradation process follows Fenton mechanism. The recyclability and stability of the PBNPs as a catalyst were also assessed, which showed that it can be used up to four cycles, demonstrating their potential for practical applications in dye wastewater treatment.