Antimonene quantum dots as bifunctional fluorescent sensors for rapid detection of cation (Fe3+) and anions (CrO42−, Cr2O72−)

Abstract

As an emerging bandgap material, antimonene quantum dots (AQDs) have attracted much attention due to their unique structure and outstanding physical and chemical properties. However, the research on the optical properties of AQDs is still in the initial stage and needs further exploration. Herein, the fluorescent AQDs were synthesized by ultrasonic liquid-phase exfoliation, combined with a hydrothermal treatment process. The as-prepared AQDs exhibit good fluorescence characteristics and have a fluorescence quantum yield value of 7.56%. Besides, the AQDs show good stability under different salt concentrations. Especially, the AQDs show high selectivity and rapid detection of Fe3+, CrO42−, and Cr2O72− ions in an aqueous solution with good anti-interference ability. The relatively low limit of detection for Fe3+ based on AQDs was 6.85 µM, and the limits of detection for CrO42−, and Cr2O72− were 23.0 and 5.91 µM, respectively. The mechanism for the fluorescence quenching of the AQDs can be attributed to the synergistic effect of the internal filter effect and the oxidation–reduction reaction between the AQDs and analytes. This work provided a simple synthesis method to easily prepare the AQDs with a larger yield, which can be applied to rapidly detect Fe3+ cation, and CrO42−, and Cr2O72− anions.