Stable silver nanoclusters with aggregation-induced emission enhancement for detection of aluminum ion

The distinct luminescence of nanoclusters (NCs) has attracted great interest in recent years. In this study, we report the synthesis of silver NCs which display aggregation-induced emission enhancement (AIEE) property. The silver NCs were prepared by a facile solid-state strategy and proved to be stable in aqueous solution. It was demonstrated that the fluorescence of the silver NCs could be heightened by aluminum ion, which permitted the silver NCs to be a fluorescence turn-on probe for aluminum ion in aqueous solution. The limit of detection (LOD) was 0.1 mu M which was much lower than the maximum concentration (7.4 mu M) of aluminum ion in drinking water permitted by the U.S. Environmental Protection Agency. The mechanism for the fluorescence enhancement of silver NCs by aluminum ion was explored based on the UV-vis absorption and dynamic light scattering experiments.