Self-dissociation-assembly Mg-Al-LDH loaded zero-valent Iron sulfide nanoparticles for efficient reduction and mineralization of TBBPA

The pervasive contamination of tetrabromobisphenol A (TBBPA) presents a critical environmental challenge due to its persistence and resistance to conventional degradation. Although sulfidized nanoscale zero-valent iron (S-nZVI) represents a promising remediation avenue, its efficacy is severely constrained by particle agglomeration and insufficient mineralization capabilities. Here, we report a self-dissociation-assembly strategy to engineer a robust S-nZVI composite supported on Mg Al layered double oxides (S-nZVI@LDO) for the substantial removal of TBBPA. By modulating the precursor synthesis pathways, we demonstrate that the hydrothermal-derived LDO support (α-phase) creates a unique nanosheet architecture that facilitates superior dispersion of reactive Fe/S species compared to chemically precipitated counterparts. The optimized S-nZVI@LDO α composite achieves >95% TBBPA removal efficiency, with a debromination efficiency of 71% and a mineralization rate of 51%, significantly outperforming traditional composites. Mechanistic investigations reveal a synergistic pathway involving rapid electrostatic adsorption, reductive debromination driven by surface-bound Fe 0 , and oxidative mineralization via in-situ generated radicals. Furthermore, the catalyst exhibits improved stability and reusability over multiple cycles. This work elucidates the critical role of precursor structural evolution in catalyst design and provides a scalable, high-efficiency solution for the remediation of halogenated organic pollutants.