Multicomponent metal-organic frameworks with aggregation-induced emission characteristics as fluorescence sensor array for the identification of energetic compounds

Abstract

The identification of energetic compounds is of great importance in the field of national security and environmental monitoring. However, due to the continuous evolution of high energy density materials, the universal discrimination strategy for energetic compounds is still very challenging. Herein, a fluorescence sensor array consisting of multicomponent metal-organic frameworks with aggregation-induced emission (AIE) characteristics is developed for distinguishing three types of energetic compounds, including nitroaromatics, nitrogen-rich heterocycles, and nitramines. Through rational design of tetraphenylethene-based AIE linkers and co-ligands, as well as selection of metal nodes, the emissive AIE metal-organic frameworks can produce unique fluorescence quenching patterns corresponding to different energetic compounds in aqueous suspensions. Nine energetic compounds are discriminated within 5 orders of magnitudes ranging from 300 μM to 10 nM by principal component analysis. The resulting sensor array demonstrates excellent selectivity against a variety of interferences and is able to simultaneously distinguish inorganic improvised explosives, providing a new approach for designing olfactory-like sensing system.