Solvent‐Engineered Synthesis of Copper Ferrite Nanocomposites From Waste PCB: Role of Diethylene Glycol in Photocatalytic Dye Degradation

The problem of pollution is worsening as an industry expands. Organic dyes are a hazardous component found in industrial wastewater. In the present research work, the effectiveness of methylene blue (MB) degradation using as‐prepared copper ferrite nanocomposite (CFN) photocatalysts was investigated via a solvothermal technique. Diethylene glycol (DEG) was used as a solvent for synthesis of CFC from obsolete printed circuit boards (PCBs) through solvothermal approach. Here, DEG was used as an efficient solvent and also a good capping agent. The DEG affects the phase formation, lattice constant, microstrain, and surface morphology properties. The synthesized samples were characterized by Fourier transform infrared (FTIR) spectroscopy, X‐ray diffraction (XRD), scanning electron microscopy with energy‐dispersive X‐ray spectroscopy (SEM‐EDX), and transmission electron microscopy (TEM), as well as UV‐visible spectroscopy to measure the percentage of MB degradation. CFC‐10 and CFC‐20 nanocomposites have optical bandgaps of 3.28 and 3.24 eV, making them suitable photocatalysts and it has shown 42.12% and 76.92% MB degradation in 180 min by UV lights. More than 93% of the CFN photocatalysts (both) were recovered successfully and can be reused without losing the photocatalytic performance. Furthermore, radical scavenging experiments showed superoxide and hydroxyl radicals were responsible for MB dye degradation. The present work reveals a sustainable waste‐to‐resource strategy by transforming outdated PCBs into reusable CFNs for industrial dye rectification, subsidizing circular material flows and combined environmental management.