An InIII-based anionic metal–organic framework: sensitization of lanthanide (III) ions and selective absorption and separation of cationic dyes

Abstract

An In^III-based anionic framework (In^III-MOF) with 4-connected SrAl₂ topology was constructed. The In^III-MOF with permanent porosity functions as a host for encapsulation of Ln³⁺ ions through ion-exchange processes. The photophysical properties of the as-prepared Ln³⁺@In^III-MOF were investigated and the results showed that the In^III-MOF could serve as an antenna to sensitize Ln³⁺ cations, especially suitable for Tb³⁺ and Eu³⁺ ions. The possible sensitization mechanism has been studied by surface photovoltage spectroscopy. Additionally, the In^III-MOF could also act as a host material when applied in the separation and purification of cationic dyes, which is highly based on the size and charge of organic dyes. Moreover, it can be used as a chromatographic column stationary phase to separate cationic dyes more efficiently and selectively. It is believed that the as-prepared In^III-MOF may have potential applications in optical materials and environmental fields.