Exploring electron-modulated dual-center confined catalysis in LDH@MoS2 membranes for enhanced organoarsenic pollution remediation

The removal of organoarsenic pollutants from water is a critical environmental challenge, and the development of effective materials and strategies for this purpose is a key area of research in sustainable treatment technologies. Herein, we developed a novel LDH@MoS2 confined catalytic membrane designed to activate peroxymonosulfate for the harmless treatment of p-arsanilic acid. The FeCo-Layered Double Hydroxide (LDH)@MoS2 membrane exhibited remarkable performance, achieving nearly 100 % removal of p-ASA at a reaction rate of 5.35 s−1 and nearly complete arsenic immobilization over 60 h of continuous operation. Experimental and theoretical results demonstrated that the electron-deficient character of LDH contracts the S-O bond length, amplifying electron density adjacent to the Fermi energy level while MoS2 with electron-rich nature and hydrophobicity facilitates charge equilibration via Mo-O/S-Fe electron bridges, together catalyzing rapid electron translocation and singlet oxygen generation. Practical applicability was validated across various water types and complex matrices, including seawater and wastewater treatment plant effluents, demonstrating high resilience to interference from inorganic ions and natural organic matter. Additionally, significant reductions in dissolved arsenic concentrations in contaminated soil were achieved, with levels falling from 2354.30 μg/L to 0.14 μg/L, well below drinking water standards. The results indicate that the LDH@MoS2 membrane represents a promising platform for effective organoarsenic remediation in various environmental contexts.