Highly sensitive and selective fluorescent probe for Ag+ based on a Eu3+ post-functionalized metal–organic framework in aqueous media

A new class of lanthanide luminescent MOFs was generated by postsynthetic modification encapsulating Eu³⁺ into the pores of MIL-121 (Eu³⁺@MIL-121). More significantly, the robust Eu³⁺@MIL-121 shows fast response and high sensitivity to Ag⁺ ions in aqueous solution, due to a great enhancement in the Eu-luminescence.