High-Yield Exfoliation of Ultrathin Two-Dimensional Ternary Chalcogenide Nanosheets for Highly Sensitive and Selective Fluorescence DNA Sensors

摘要

High-yield preparation of ultrathin two-dimensional (2D) nanosheets is of great importance for the further exploration of their unique properties and promising applications. Herein, for the first time, the high-yield and scalable production of ultrathin 2D ternary chalcogenide nanosheets, including Ta_2NiS_5 and Ta_2NiSe_5, in solution is achieved by exfoliating their layered microflakes. The size of resulting Ta_2NiS_5 and Ta_2NiS_5 nanosheets ranges from tens of nanometers to few micrometers. Importantly, the production yield of single-layer Ta_2NiS_5 nanosheets is very high, ca. 86%. As a proof-of-concept application, the single-layer Ta_2NiS_5 is used as a novel fluorescence sensing platform for the detection of DNA with excellent selectivity and high sensitivity (with detection limit of 50 pM). These solution-processable, high-yield, large-amount ternary chalcogenide nanosheets may also have potential applications in electrocatalysis, supercapacitors, and electronic devices.