title: Graphene-Based Fluorescence-Quenching-Related Fermi Level Elevation and Electron-Concentration Surge.
abstract: Intermolecular p-orbital overlaps in unsaturated π-conjugated systems, such as graphene and fluorescent molecules with aromatic structure, serve as the electron-exchanged path. Using Raman-mapping measurements, we observe that the fluorescence intensity of fluorescein isothiocyanate (FITC) is quenched by graphene, whereas it persists in graphene-absent substrates (SiO2). After identifying a mechanism related to photon-induced electron transfer (PET) that contributes to this fluorescence quenching phenomenon, we validate this mechanism by conducting analyses on Dirac point shifts of FITC-coated graphene. From these shifts, Fermi level elevation and the electron-concentration surge in graphene upon visible-light impingements are acquired. Finally, according to this mechanism, graphene-based biosensors are fabricated to show the sensing capability of measuring fluorescently labeled-biomolecule concentrations.
authors: Department of Physics, State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center for Optoelectronic Semiconductors and Efficient Devices, Xiamen University , Xiamen 361000, China.
authors: Weiyi
authors: W
authors: Lin
authors: Department of Physics, State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center for Optoelectronic Semiconductors and Efficient Devices, Xiamen University , Xiamen 361000, China.
authors: Bo
authors: B
authors: Tian
authors: Department of Physics, State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center for Optoelectronic Semiconductors and Efficient Devices, Xiamen University , Xiamen 361000, China.
authors: Pingping
authors: P
authors: Zhuang
authors: Pen-Tung Sah Institute of Micro-Nano Science and Technology, Xiamen University , Xiamen 361005, China.
authors: Jun
authors: J
authors: Yin
authors: Department of Physics, State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center for Optoelectronic Semiconductors and Efficient Devices, Xiamen University , Xiamen 361000, China.
authors: Cankun
authors: C
authors: Zhang
authors: Department of Physics, State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center for Optoelectronic Semiconductors and Efficient Devices, Xiamen University , Xiamen 361000, China.
authors: Qiongyu
authors: Q
authors: Li
authors: Department of Physics, State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center for Optoelectronic Semiconductors and Efficient Devices, Xiamen University , Xiamen 361000, China.|Institute for Complex Adaptive Matter, University of California , Davis, California 95616, United States.
authors: Tien-Mo
authors: TM
authors: Shih
authors: Department of Physics, State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center for Optoelectronic Semiconductors and Efficient Devices, Xiamen University , Xiamen 361000, China.
authors: Weiwei
authors: W
authors: Cai
keywords: Dirac-point shift; Graphene; Raman mapping; electrons transfer; fluorescence quenching; π−π stacking