LAUSR

Lanthanide metal-organic framework (Ln-MOF) luminescent sensors monitoring the H2O content in D2O are still rare. We designed and built a hydrophilic mixed Ln-MOF (Eu0.4Tb0.6-MOF) monitoring the H2O content in D2O. By designing a ligand and controlling the synthesis method, we achieved a balance between the structural stability and sensing capacity. When the H2O content ranges from 0 to 100%, the photoluminescence color of Eu0.4Tb0.6-MOF can change from yellow to green, which can be observed by the naked eye. The mechanism is that the photoluminescence intensity of Eu3+ decreases faster than that of Tb3+ when the H2O content increases. The sensing mechanism was studied further by transient fluorescence spectrometry.