Cyclodextrin Functionalized Carbon Dots Using IFE and FRET Dual Mechanism for Sequential Detection of Morin and Al3+

Abstract Carbon dots (CDs) are emerging photoluminescent materials with excellent optical properties. However, the lack of active sites in primitive CDs has limited their development applications. Herein, functionalized carbon dots (Z‐CDs) are successfully prepared by surface modification of CDs with mono (6‐amino‐6‐deoxy) cyclodextrin (β‐CD). The introduction of β‐CD increases the spatial potential resistance between CDs, which effectively reduces the self‐quenching effect. Moreover, the conjugated domains of Z‐CDs are expanded, which improves the optical properties with a quantum yield of 48.74%. Z‐CDs are able to be used in the sequential detection of morin and Al 3+ , and the fluorescence mechanisms are confirmed to be internal filtration effect and fluorescence resonance energy transfer, respectively. The limits of detection are 0.817 and 0.231 × 10 −6 m . This study not only provides an idea to solve the problem of self‐quenching of CDs but also enriches the detection means of flavonoids and ions, which is expected to be applied to biosensing and environmental monitoring.