ABSTRACT
Graphene, a single atomic sheet and two-dimensional carbonaceous material, has attracted great attention for sensor applications due to its intrinsic electrical and physical properties. Many studies have shown the high sensitivity of graphene-based sensors resulting from the intrinsic properties of graphene, in applications such as pH, DNA, and vapor sensors, among others. In this chapter, we focus on the different types of graphene devices for biomolecule and gas sensing, which are relevant to biological and chemical detection. We will discuss the different working principles for corresponding sensors. Functionalization of graphene with different chemicals via various methods is critical to fabricate sensors with high selectivity. The sensitivity dependence of graphene charge transport on electron-withdrawing or electron-donating chemical groups leads to their applications as ultrasensitive chemical sensors and biosensors. We summarized typical examples of functionalization with p or n doping effect and hopefully this will motivate readers to digest and explore more functional molecules for sensing applications.
