Development and characterization of nanocarbon-based devices for sensing applications

Abstract

The subject of this PhD thesis has been the development and characterization of nanocarbon-based sensors, with particular attention to the use of easy and cheap methodologies and processes that are required for future large scale production (dielectrophoresis, lift-off, etc..). In the first part of the thesis the development of Carbon nanotubes (CNTs)-based devices for biosensing applications is reported and the tests on protein detection are shown. In the second part the development of Graphene oxide (GO)-based devices is shown and the electrical behavior of the devices is investigated in different ambient conditions and for different oxygen functionalization (GO and reduced GO).

The thesis work is divided as follows:

In the first chapter the Carbon-like materials basics are recalled. In particular the types, the properties, and the main synthesis methods are described;

The second chapter introduces the FET/Resistor devices and then describes the most common CNTs/GO structures in literature;

In the third chapter, the methods for devices preparation are described with a focus on the dielectrophoretic process, used for the deposition of the carbon-based sensitive layers. Therefore, the characterization of the devices and the sensing properties achieved as immunosensors, or humidity/temperature and volatile organic compounds (VOC) sensors are shown and discussed;

Finally, in the conclusions the main results, work in progress, developments and future applications are discussed.