Tuning the high-energy state of Fe-GLC via high salinity stacking effect for ECs spontaneous destruction in waters.

Achieving cost-effective removal of organic contaminants in saline wastewater remains a persistent global challenge. Current advanced oxidation processes based on reactive oxygen species suffer from unsatisfactory efficiency and substantial energy demands. Herein, we synthesized a Fe coordinated chlorapatite (CAP)-doped graphene-like structure catalyst (Fe-GLC) with cation-π interactions. Fe-GLC exhibited high efficiency and stability for various emerging contaminants (ECs) degradation without additional energy input, and even achieved 100% removal for BPA in municipal wastewater and high-salinity pesticide wastewater (3.5%). The reaction rate was increased by 1.14 to 1.81 fold with 100 mM∼400 mM salinity. The stacking effect of salinity on GLC π system effectively induced surface charge rearrangement and stronger electric field, thus opening the charge transfer channels of ECs → GLC → Fe species and forming more high-spin Fe species and highly compressed GLC π system. This significantly increased electric field energy and weakened the bond energy of ECs, thereby initiating spontaneous surface destruction of ECs under the action of O2 as the electron acceptor. Our findings highlight the potential of utilizing salinity-mediated surface multicomponent synergistic coordination to regulate the high-energy state of catalysts, offering a promising avenue for developing sustainable and cost-effective novel technologies for ECs purification in high-salinity wastewater.