Solvent-free synthesis of hierarchical Tb^(3+)-doped Yttrium benzene-1,3,5-tricarboxylate metal organic framework nanosheets for fast and highly sensitive fluorescence detection of Fe3+and Cr2O72−ions

Controllable synthesis of luminescent metal-organic frameworks (MOFs) having the merits of ease preparation, outstanding sensitivity and stability is of great significance for exploring their efficient sensing applications. Herein, we report a hierarchical terbium-doped yttrium-benzene-1,3,5-tricarboxylate MOF nanosheet via solvent-free synthetic strategy with a topological structure of MIL-78. The fluorescence property of the hierarchical Tb^(3+)-doped Y-based MOF nanosheets can be tuned by adjusting the molar ratio of Tb^(3+) to Y^(3+) ions, and the Tb_(0.5)Y_(0.5)-MOF nanosheet-like morphology with the optimum characteristic Tb^(3+) ion green emission exhibited great potential acting as fluorescence probe for highly sensitive Fe^(3+) and Cr_(2)O_(7)^(2−) detection. The Tb^(3+)-doped Y-MOF nanosheets show a fast response time of less than 1 s for Fe^(3+) ions. They also have low detection limits of 0.40 and 0.26 µM toward Fe^(3+) and Cr_(2)O_(7)^(2−) ions, respectively, as well as excellent stability. This work paves the way to explore intriguing hierarchical MOF-based luminescent materials for efficient fluorescence sensing applications.