Biomass Carbon Dots as Fluorescent Probes for Fast and Highly Selective Detection of Fe in Water Media.

In this study, a novel fluorescent probe for the rapid and highly selective detection of Fe based on biomass carbon dots (b-CDs) was developed. The b-CDs were obtained via one-step hydrothermal synthesis by utilizing laurel fallen leaves. And the as-synthesized b-CDs were applied for sensing Fe based on fluorescence (FL) quenching effect both in water and phosphate buffer solution (PBS) with a wide linear range from 1 µM to 300 µM, the detection limits (LODs) respectively to be 0.34 µM in water and 0.48 µM in PBS solution. The FL intensity of b-CDs was quenched fleetly within 1 min after adding Fe. The sensing mechanism of the b-CDs + Fe system can be attributed to the internal filtration effect (IFE) mechanism and the electron transfer (ET) between b-CDs and Fe in water, and only the IFE mechanism in PBS solution based on multiple experimental evidences. Moreover, the as-proposed probe was successfully adopted for monitoring Fe in lake water and tap water samples. This research shows some merits of economic, simplicity, green, high selectivity, and quick response for Fe determination, and provides an approach for the water quality monitoring of Fe and the effective utilization of waste biological materials.