Synthesis of a Molecularly Imprinted Magnetic Core–Shell Photocatalyst for Efficient Micropollutant Removal

The removal of persistent micropollutants, such as pharmaceutical residues, agricultural chemicals, and industrial contaminants from wastewater is a rising concern nowadays. Conventional wastewater treatment methods are often ineffective in completely eliminating these contaminants. Owing to their high degradation efficiency, environmental compatibility, and the potential for solar-driven operation, advanced oxidation processes (AOPs), particularly photocatalysis, have shown great promise for the efficient degradation of pharmaceutically active compounds. The selectivity and subsequent removal of the photocatalyst from the suspension were addressed in this work by assembling a magnetic core–shell photocatalyst with a molecular imprint of torasemide via microwave-assisted synthesis. The embedded magnetite allows for simple and effective retrieval of the photocatalyst using an external magnet, ensuring reusability. Meanwhile, the molecularly imprinted TiO₂ layer provides highly specific binding sites for the target molecule, boosting adsorption selectivity and photocatalytic performance. Moreover, microwave irradiation facilitated rapid and uniform heating, promoting accelerated nucleation and particle growth, reducing reaction time, and enhancing energy efficiency. The obtained photocatalyst exhibited 84% degradation of torasemide in 120 mins, as opposed to non-imprinted photocatalyst with only 12% degradation. The structural and surface properties of the synthesized material were investigated using X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). Nitrogen adsorption–desorption isotherms (BET) were used to determine the specific surface area and pore characteristics. Band gap energy was evaluated using diffuse reflectance spectroscopy (DRS), and the morphology of the material was examined via scanning electron microscopy (SEM).