Enhancement of fluorescence brightness and stability of copper nanoclusters using Zn2 + for ratio-metric sensing of S2 −

It is acknowledged water soluble copper nanoclusters (Cu NCs) are extremely unstable in aqueous solutions, which limit their fluorescence applications to a great extent. In this work, it is found the fluorescence intensity and stability of water soluble Cu NCs could obviously be enhanced by the introduction of Zn2 +. Then, the as modified Cu NCs will be stable enough to be applied as a ratio-metric sensor for S2 −. This method may provide more broaden avenues for the application of fluorescent Cu NCs in the future.