The synthesis of Cu nanoclusters and their dual mode colorimetric and fluorescent sensing for 2,4-dinitrophenol.

Herein, we have reported a facile one-pot strategy to synthesize fluorescent Cu nanclusters (Cu NCs) by using ʟ-histidine as stabilizer, and ascorbic acid as reducing agent. Cu NCs are stable, water-dispersible, and emit bright cyan emission with a quantum yield 26.08%. The Cu NCs can be employed as colorimetric and fluorimetric dual-mode detector, exhibiting excellent selectivity and sensitivity for detecting 2,4-dinitrophenol (DNP) specifically. Notably, Cu NCs were a sensitive sensor, which had speciality to detect DNP in range of linearity from 0.01 to 0.15 mM with a discernable limit as low as 3.96μM. The mechanism of efficiently selective detection of DNP by Cu NCs was analyzed by UV absorption, fluorescence decay spectrum, and the performance of 'turn off' towards DNP was determined as the inner filter effect and static quenching effect. Further, the environmental tolerance of the Cu NCs probe was estimated by using the different natural water samples, demonstrating its great promise in the field of DNP monitoring and water sample analysis.