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Graphene-Based Optical Biosensors and Imaging
Zhiwen Tang, Shijiang He, Hao Pei, Dan Du, Chunhai Fan, and Yuehe Lin
5.1 Introduction
Graphene is the fundamental building element of many carbon allotropes including
graphite, charcoals, carbon nanotubes, buckminsterfullerene, and other buckyballs, etc.
Graphene comprises a single layer of six-atom rings in a honeycombed network and can
be conceptually considered as a true planar aromatic macromolecule.
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Interestingly the
theory of graphene was explored in 1947 and scientists believed that graphene could not
exist by itself due to thermodynamic instability at the nanometer scale. Though scienti ...