Chemosensing properties and logic gate behaviors of graphene quantum dot-appended terpyridine.

Graphene quantum dot-covalently appended terpyridine, GQDs–tpy, was synthesized and characterized by X-ray photoelectron spectroscopy, FTIR spectroscopy and transmission electron microscopy. GQDs–tpy was found to act as multifunctional chemosensors: a highly selective colorimetric chemosensor for Fe2+ as evidenced by an obvious color change from colorless to pink, and a typical fluorescence enhanced probe for Zn2+ over 13 metal cations even in practical water samples. Moreover, two-input XOR, INHIBIT and IMPICATION logic gates as well as four-input OR and NOR logic gates were constructed according to the characteristic responses of GQDs-tpy to a sequence of cations.