Synthesis of a Luminescent Aluminum-Based MOF for Selective Iron(III) Ion Sensing

In the search for new materials to open up creative pathways for industry and research, modifi-cation is one of the best methods to implement. Developing materials with high sensitivity and selectivity for specific applications, such as ion sensing, remains a significant challenge. This work aims to introduce a novel Metal-organic framework (MOF) derived from the well-established 2-amino-[1,1'-biphenyl]-4,4'-dicarboxylic acid MOF by modifying its structure to enhance its properties and applications. A luminescent 2-naphthyl moiety was attached to the amino group of the linker to form the new luminescent Al-based MOF Al-BP-Naph with a surface area of 456 m2·g–1 and a pore volume of 0.55 cm3·g–1. Al-BP-Naph showed high selectivity towards Fe+3 sensing due to the overlapping absorption and excitation spectra of both Fe3+ and MOF. The MOF demonstrated a detection limit of approximately 6·10–6·mol L-1 with a limit of quantification of about 19·10–6·mol L–1 and a very fast response time (less than 10 seconds). It also had a Stern-Volmer constant of approximately 0.09·105 L·mol–1 , distinguishing it from other ions. Our work contributes to the expanding repertoire of functional materials with promising applications in sensing technologies, offering a novel MOF with superior properties for iron(III) ion detection.