Fluorescent Nanoprobe Based on Ex_g‐C₃N₄ for Highly Selective and Fast‐Response Aluminum Detection in Water Samples

Abstract The development of a simple and efficient sensor for detecting aluminum (Al) ion is fundamentally essential for environmental monitoring and human health protection. In this study, a luminescent sensor Ex_g‐C₃N₄ was prepared by thermal oxidation exfoliation g‐C₃N₄, and the application of Ex_g‐C₃N₄ for detecting Al 3 ⁺ ion in water was explored. The results showed that Ex_g‐C₃N₄ exhibits fluorescence quenching effect on Al 3+ with high selectivity and sensitivity in water. Ex_g‐C₃N₄ displayed its high efficiency for the fluorescence detection of Al 3+ with a response time of 10 s and an extraordinary limit of detection of 5.75 nM for the detection range was 0–63 mM in water. Moreover, a portable fluorescent test strip for the rapid detection of Al 3+ was successfully developed based on Ex_g‐C₃N₄, which can rapidly and conveniently detect Al 3+ ion in solutions, as the detection limit of 1.0 µM is low enough to meet the safety requirements in drinking water. Furthermore, the fluorescence quenching mechanism of Ex_g‐C₃N₄ for Al 3+ ion in water was also discussed.