A dual-fluorescent composite of graphene oxide and poly(3-hexylthiophene) enables the ratiometric detection of amines

A composite prepared by grafting a conjugated polymer, poly(3-hexylthiophene) (P3HT), to the surface of graphene oxide was shown to result in a dual-fluorescent material with tunable photoluminescent properties. Capitalizing on these unique features, a new class of graphene-based sensors that enables the ratiometric fluorescence detection of amine-based pollutants was developed. Moreover, through a detailed spectroscopic study, the origin of the optical properties of the aforementioned composite was studied and was found to be due to electronic decoupling of the conjugated polymer from the GO. The methodology described herein effectively overcomes a long-standing challenge that has prevented graphene based composites from finding utility in sensing and related applications.