Unlocking the power of MgFe-LDHcal/TiO2 heterojunctions for superior photocatalytic detoxification of industrial wastewater

Reactive dyes are widely used by the textile industry to color fabrics such as wool, cotton, and viscose. The persistence of these dyes in effluents poses significant environmental concerns due to their cytotoxic, mutagenic, and carcinogenic properties, as well as their ability to inhibit mitochondrial functions. This study presents the first-ever report on the synthesis and photocatalytic application of MgFe-LDHcal/TiO₂ heterojunctions for the efficient detoxification of industrial wastewater. The novel composite leverages the synergistic properties of MgFe-Layered Double Hydroxides (LDH) in their calcined form (LDHcal) and titanium dioxide (TiO₂), resulting in a material with enhanced photocatalytic performance. MgFe-LDHcal provides a high surface area, strong adsorption capacity, and excellent electron mobility, while TiO₂ is renowned for its ability to generate reactive oxygen species under light irradiation. In this study, the MgFe-LDHcal/TiO₂ heterojunction was applied directly to industrial wastewater, achieving remarkable detoxification efficiency by degrading persistent organic pollutants. The composite demonstrated superior photocatalytic activity under visible light, making it suitable for practical, large-scale industrial applications. This study focuses on the photocatalytic degradation of various reactive dyes, including Reactive Green 19, Reactive Red 120, Reactive Blue 4, and Eosin Yellow, using a nanocomposite of TiO 2 /MgFe-LDHcal. For the first time, the photocatalytic performance of this heterojunction material was evaluated for degradation of these reactive dyes under visible light irradiation. Remarkably, the system achieved complete dye detoxification of highly concentrated waste water within 1 hour. The heterojunction was thoroughly characterized using powder X-ray diffraction (XRD) to confirm the crystalline structure and composite formation. UV-Visible and photoluminescence (PL) spectroscopy were conducted to assess the optical properties and photocatalytic activity under light exposure. High- resolution transmission electron microscopy (HR-TEM) was used to examine particle size, interplanar spacing, and morphology. Additionally, the rejuvenation studies demonstrated that the MgFe-LDHcal/TiO 2 heterojunction can be reused for multiple cycles, highlighting its potential as a sustainable and effective photocatalyst for industrial wastewater treatment.