Chemical functionalization of single-walled carbon nanotube field-effect transistors as switches and sensors

Because of the one-dimensional (1D) nanostructural nature of single-walled carbon nanotubes (SWNTs) and their advantages of chemical flexibility and sensitivity arising from the susceptibility of their active surfaces to interacting species, great effort has been made to integrate carbon nanotube field-effect transistors (NTFETs) into functional optoelectronic devices capable of converting external stimuli to easily detectable electrical signals. In this Review article, we aim to capture recent advances of rational design and chemical functionalization of NTFETs for the purpose of switching or biosensing applications. To provide a deeper understanding of the device responses to analytes, this review will also survey the proposed sensing mechanisms. As demonstrated by these remarkable examples, the concept of combining the proper selection of functional molecular materials and molecular self-assembly with device micro/nanofabrication offers attractive new prospects for constructing NTFET-based molecular optoelectronic devices with desired functionalities.