Tuning Energy Transfer in Metal‐Organic Frameworks for Fluorescence Turn‐on Sensing of Hg(II) Ions†

Comprehensive Summary Tuning Förster resonance energy transfer (FRET) in metal‐organic frameworks for fluorescence turn on sensing is rarely reported. Herein, we designed and synthesized several FRET‐based metal‐organic frameworks (MOFs) with different donor/acceptor ratios. Through the oxidation of the acceptor, the FRET process in MOFs can be efficiently modulated so as to turn‐on the fluorescence of the framework in a controlled manner. Interestingly, the MOF with an optimized donor/acceptor ratio of 7.0 was used as an efficient fluorescence turn on sensor for Hg(II) ions with good sensitivity and selectivity. We believe our present study will not only give a useful method to construct fluorescence turn‐on sensors but also trigger the construction of novel FRET‐based MOFs for the fluorescence turn‐on sensing of target analytes in the future.