| 초록 |
In this work, a green and simple one-pot rout was developed for the synthesis of amino-functionalized graphene quantum dots (a-GQDs) via hydrothermal process without any further modification or surface passivation. The as-obtained a-GQDs have a uniform size of 3-4 nm, high contents of amino groups, and show a bright green emission with high quantum yield of 32.8%. Furthermore, the a-GQDs show effective fluorescence quenching for Cu2+ ions which can serve as effective fluorescent sensors for the detection of Cu2+. The fluorescent sensor using the obtained a-GQDs exhibits high sensitivity and selectivity toward Cu2+ with the limit of detection as low as 5.6 nM. The mechanism of the Cu2+ induced fluorescence quenching of a-GQDs can be attributed to the electron transfer by the formation of metal complex between Cu2+ and the amino groups on the surface of a-GQDs. |
