title: Optical bifunctionality of europium-complexed luminescent graphene nanosheets.
abstract: Graphene is an intriguing two-dimensional material, which could be modified for achieving tunable properties with many applications. Photoluminescence of graphene due to plasmonic emission is well-known, however, attempts to develop strong luminescent graphene have been difficult. Synthesis of a graphene-based material with a dual optical functionality, namely quenching the fluorescence of organic dyes while maintaining its own self-luminescence, is an interesting and challenging proposition. Here, we demonstrate this optical bifunctionality in a lattice-modified luminescent graphene, where europium(III) cations are complexed with graphene through oxygen functionalities. After excitation at 314 nm, a hypersensitive red emission is observed at 614 and 618 nm showing the complexation of europium(III) with graphene. We demonstrate dual functionality of this graphene by the quenching of luminescence of Rhodamine-B while displaying its own hypersensitive red emission. The decay lifetime observed through the time-resolved spectroscopy confirms its potential for applications in biosensing as well as optoelectronics.
authors: Department of Mechanical Engineering and Materials Science, Rice University, 6100 Main Street, Houston, Texas 77005, United States. bipinbhu@yahoo.com
authors: Bipin Kumar
authors: BK
authors: Gupta
authors: Palanisamy
authors: P
authors: Thanikaivelan
authors: Tharangattu N
authors: TN
authors: Narayanan
authors: Li
authors: L
authors: Song
authors: Wei
authors: W
authors: Gao
authors: Takuya
authors: T
authors: Hayashi
authors: Arava Leela Mohana
authors: AL
authors: Reddy
authors: Avishek
authors: A
authors: Saha
authors: Virendra
authors: V
authors: Shanker
authors: Morinobu
authors: M
authors: Endo
authors: Angel A
authors: AA
authors: Martí
authors: Pulickel M
authors: PM
authors: Ajayan
mesh_terms: D005063:Europium / Q000737:chemistry*; D006108:Graphite / Q000737:chemistry*; D049449:Luminescence; D049408:Luminescent Agents / Q000737:chemistry*; D049329:Nanostructures / Q000737:chemistry*; D010100:Oxygen / Q000737:chemistry
chemical_list: D049408:Luminescent Agents; D005063:Europium; D006108:Graphite; D010100:Oxygen