Cu nano-armor supported on Ti Metal-Organic Frameworks: A stable catalyst for enhanced photocatalytic water disinfection

Abstract

The rapid spread of microbial contamination and drug-resistant bacteria poses a significant threat to ecosystems and public health, highlighting the urgent need for efficient and stable disinfection materials. Metal-organic frameworks (MOFs) have emerged as promising functional materials for a variety of applications due to their regular microstructure and excellent physicochemical properties. However, their long-term use is limited by intrinsic instability. In this study, we designed copper nanolayers as protective armor for titanium-based MOFs (Cu/Ti-MOFs) to enhance their catalytic performance in photocatalytic disinfection under visible-light irradiation. The results demonstrated that Cu/Ti-MOFs exhibited slightly improved antimicrobial activity against Escherichia coli (E. coli), Staphylococcus aureus, and tetracycline-resistant E. coli compared to Ti-MOFs. More importantly, Cu/Ti-MOFs retained 92 % of their initial activity after seven consecutive catalytic cycles, whereas Ti-MOFs completely lost their photosensitive properties, indicating much higher catalytic stability of Cu/Ti-MOFs. This improvement was confirmed through various physicochemical characterizations and was attributed to the protection of active sites, catalyst reinforcement, and efficient surface reconstruction due to the introduction of the Cu nanolayer. This study provides a strategy for enhancing the long-term performance of MOF materials in photocatalytic water disinfection applications.