Nanoscale Patterning of Carbon Nanotubes: Techniques, Applications, and Future

Abstract

Carbon nanotube (CNT) devices and electronics are achieving maturity and directly competing or surpassing devices that use conventional materials. CNTs have demonstrated ballistic conduction, minimal scaling effects, high current capacity, low power requirements, and excellent optical/photonic properties; making them the ideal candidate for a new material to replace conventional materials in next-generation electronic and photonic systems. CNTs also demonstrate high stability and flexibility, allowing them to be used in flexible, printable, and/or biocompatible electronics. However, a major challenge to fully commercialize these devices is the scalable placement of CNTs into desired micro/nanopatterns and architectures to translate the superior properties of CNTs into macroscale devices. Precise and high throughput patterning becomes increasingly difficult at nanoscale resolution, but it is essential to fully realize the benefits of CNTs. The relatively long, high aspect ratio structures of CNTs must be preserved to maintain their functionalities, consequently making them more difficult to pattern than conventional materials like metals and polymers. This review comprehensively explores the recent development of innovative CNT patterning techniques with nanoscale lateral resolution. Each technique is critically analyzed and applications for the nanoscale-resolution approaches are demonstrated. Promising techniques and the challenges ahead for future devices and applications are discussed.

Characterization of Silver Nanowire-Based Transparent Electrodes Obtained Using Different Drying Methods

“…For example, it has been reported that Ag nanowire-based hybrid electrodes comprising Ag nanowires, carbon nanotube, and graphene oxide can achieve efficient wearable sensors [ 21 ] and organic photovoltaics [ 22 ]. In addition, the electrospray assisted etching of Ag nanowires was able to fabricate a quasi-periodic structure with the potential for various optoelectronic applications [ 23 ] and several patterning methods for Ag nanowires including subtractive methods, additive methods and printing methods were developed to achieve a precise patterning of Ag nanowire networks [ 24 , 25 ]. To this end, we recently adopted AgNWs as metal top electrodes and fabricated a transparent speaker that could be attached to a display [ 26 ].…”

Insights on functionalized carbon nanotubes for cancer theranostics

“…Of course, every coin has two sides, the distinctive structures of CNTs increase their hydrophobicity in water and leave them with inherent cytotoxicity [ 29 ]. Therefore, elevating hydrophilicity and reducing cytotoxicity through functionalizing CNTs with different chemical groups or biomolecules are of great significance to improve their safety and effectiveness for broad application in cancer therapy [ 30 ]. Thus, this review highlights the update progress of CNTs as promising drug delivery vehicles in cancer treatment.…”

Thickness/morphology of functional material patterned by topographical discontinuous dewetting

“…Controlling the wettability can be done by controlling the chemistry of the substrate surface to make hydrophilic/hydrophobic patterns, and this has been researched extensively. [ 15–18 ] However, the wettability can also be controlled by the substrate surface topography. “Topographical” discontinuous dewetting (TDD) has been used to selectively fill patterned, open cavities with functional inks, depositing the functional materials into the open cavities in desired patterns.…”