Enhanced electrochemical and photocatalytic performance achieved through dual incorporation of SnO2 and WO3 nanoparticles into LDH layer fabricated on PEO-coated AZ31 Mg alloy

This study explores the potential of LDH flakes decorated with metallic oxide nanoparticles to function as both anti-corrosion barriers against chloride anions and heterogeneous photocatalysts for tetracycline degradation under visible light. The process involves modifying the primarily MgO-based inorganic porous film by growing a MgFe LDH film, followed by the individual and dual incorporation of SnO2 and WO3 nanoparticles. The dual incorporation of these nanoparticles into the LDH matrix leads to synergistic interactions, effectively sealing pre-existing defects within LDH flakes and facilitating the in-situ formation of catalytic sites through oxidation and the induction of surface oxygen vacancy defects, which synergistically contribute to the enhancement of both electrochemical and photocatalytic activities. The enhanced electrochemical stability is reflected in a significant reduction in corrosion current density by 4 orders of magnitude compared to unmodified porous film. Additionally, the decorated film demonstrates sustained photocatalytic functionality, achieving significant degradation (95.5 %) of tetracycline within two hours. This study presents a novel approach, highlighting the dual effectiveness of LDHs decorated by dual metal oxides as an anti-corrosive agent and photocatalyst, with promising implications for environmental remediation and wastewater purification.