Green biosynthesis of hybrid Zn – Al LDH /iron oxide–hydroxide nanoparticles from acid mine drainage using Phlomis herba‐venti L .: Structural characterization with high‐performance F enton‐type and photocatalytic dye degradation

Abstract This work introduces a new, environmentally friendly approach to the direct synthesis of hybrid nanoparticles and layered double hydroxide (LDH) through the valorization of acidic mine drainage (AMD) as a cost‐free metal precursor and the use of Phlomis herba‐venti extract as a biogenic reducing and capping agent, eliminating the need for conventional chemical synthesis reagents. Comprehensive physicochemical characterization was conducted using UV–Vis spectroscopy, scanning electron microscopy coupled with energy‐dispersive X‐ray spectroscopy (SEM–EDX), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and X‐ray diffraction (XRD). Structural analyses based on XRD, TEM, and SEM–EDX revealed the formation of a hybrid layered double hydroxide (LDH)–nanocomposite system with an average particle size of 58.33 ± 13.31 nm. Elemental analysis by EDX confirmed the predominance of iron (Fe), zinc (Zn), and aluminium (Al) species within the nanostructures. FTIR spectra exhibited characteristic absorption bands substantiating the dual role of the Phlomis herba‐venti extract as a reducing agent and a stabilizing matrix for AMD‐derived metal ions. The resulting (AMD)NPs demonstrated outstanding catalytic performance in wastewater treatment applications, achieving 99% removal within 60 min via Fenton‐type oxidation and 90% removal within 120 min under heterogeneous photocatalytic conditions. Overall, this work establishes a sustainable and circular framework in which plant‐mediated green chemistry is synergistically integrated with AMD waste recovery to generate high‐performance catalytic nanomaterial for environmental and potential industrial applications.