Carbon nanotube electronics for IoT sensors

The Internet of Things (IoT) is the concept of a ubiquitous computing ecosystem in which electronics of custom form factors are seamlessly embedded into everyday objects. At the heart of the IoT are electronic sensors capable of detecting physical/environmental phenomena, translating these measurements into electrical signals, and wirelessly transmitting the data for remote computing. Critical to the development of IoT sensors and systems are low-cost materials, robust enough to sustain stable electrical performance over medium to long periods of time, yet sensitive enough to detect small changes in the surrounding environment. Such materials should be mechanically flexible and amenable to solution-based processing to facilitate large scale production methods, such as roll-to-roll printing. Carbon nanotubes (CNTs) are one of the leading material candidates to satisfy these requirements because of their unique electrical and mechanical properties, which enable robust and versatile devices, in combination with their chemical properties, which allow for the processing of CNTs from solution. These advantages have enabled demonstration of a myriad of printed CNT-based electronics and sensors on diverse substrates with wide ranges of functionality, spanning from simple sensors based on passive devices to complex multi-stage circuitry and display electronics. In this review, we provide a comprehensive summary of the CNT-based electronics and sensor space with an emphasis on applications aligned with the IoT. Primary coverage is devoted to devices consisting of randomly oriented CNT networks; however, the advantages and capabilities of single-nanotube devices will also be discussed. Key works across various types of sensors will be reviewed and a summary of the remaining challenges for CNT-based sensor technologies will be presented.

Duke Scholars

Author Steven Noyce Electrical and Computer Engineering

Author Aaron D. Franklin Electrical and Computer Engineering