Recent advances in fluorescent metal organic framework based detection of heavy metal contaminants in water

Heavy metal contamination of the water sphere poses a grave threat to environmental safety as well as wellbeing of human and other species. Heavy metal ions (HMI) such as Pb²⁺, Hg²⁺, Cd²⁺, Cr⁶⁺, As³⁺, Ni²⁺, Cu²⁺, regularly form potentially damaging industrial waste constituents that severely affect marine and human life. Excess Fe³⁺ ions in water can also pose a risk to human health. Detection methodologies are essential before taking action. The design and development of highly selective, sensitive methods for detecting such harmful ions would be a crucial step toward resolving water pollution. Due to their high surface area, porosity and functionalized structures metal organic frameworks (MOFs) turned into a versatile platform for the detection of HMIs. This review provides an overview of various MOF based detection mechanisms, including fluorescence sensing and quenching, along with their sensitivity, selectivity, and applicability in real world scenarios. Important developments in the design, structure, and functionalization of MOFs will also be included. The aims of this work are twofold: first, to provide a firm understanding of luminescent MOFs and their mechanisms for detecting HMIs; and second, to serve as a launch-pad for future innovations in this important area.