Solvent- and pH-Stable Eu(III)-Based Metal–Organic Framework with Phosphate-Ratio Fluorescence Sensing and Significant Proton Conduction

to be used as a ratiometric fluorescent sensor for phosphate efficiently and rapidly, with a limit of detection of 0.12 μM in the Tris-HCl buffer solution. These results provide a new approach for the construction of MOFs with high proton conductivity and a ratiometric fluorescence response.