▎ 摘　　要

A functional hybrid of graphene quantum dots (GQDs) and cobalt pyrene-derivatized phthalocyanine (CoPc) used as a sensitive nanoprobe for the recognition of cyanide ion (CN-) is described in this work. The fluorescence of GQDs was quenched upon non-covalent (pi-pi stacking) hybrid formation with CoPc via a possible energy transfer pathway. However, in the presence of CN-, the interaction between GQDs and CoPc was perturbed, such that the fluorescence of GQDs initially quenched by CoPc was found to be efficiently recovered in the presence of CN-. Amongst the molecules and anions tested to ascertain their effects on the fluorescence behaviour of the hybrid, only CN- ion induced the tunable "off-on" restoration of the fluorescence of GQDs, which demonstrates the selectivity of the hybrid towards CN-. The restored fluorescence signals of the GQDs were linearly modulated by different concentrations of CN- and were used for the quantitative assay of CN- with high sensitivity coupled with rapid detection time. The detection was in the linear range of 1.0-50.0 nM with limits of detection (LOD) of 0.5 nM. The analysis of spiked samples for the recovery of CN- further demonstrated the applicability of the hybrid for the satisfactory detection of the target analyte.