Solvent-free synthesis of hierarchical Tb3+-doped Yttrium benzene-1,3,5-tricarboxylate metal organic framework nanosheets for fast and highly sensitive fluorescence detection of Fe3+ and Cr2O72− ions

Abstract

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 Tb3+-doped Y-based MOF nanosheets can be tuned by adjusting the molar ratio of Tb3+ to Y3+ ions, and the Tb0.5Y0.5-MOF nanosheet-like morphology with the optimum characteristic Tb3+ ion green emission exhibited great potential acting as fluorescence probe for highly sensitive Fe3+ and Cr2O72− detection. The Tb3+-doped Y-MOF nanosheets show a fast response time of less than 1 s for Fe3+ ions. They also have low detection limits of 0.40 and 0.26 µM toward Fe3+ and Cr2O72− 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.

Keywords

• Rare earth-MOF
• Hierarchical nanosheet-like morphology
• Fluorescence sensing
• Fast response