DPN-Mediated Chemical Surface Patterning on Graphene

Illustration of the atomic structure of graphene

Introduction

Using a bottom-up Dip Pen Nanolithography® (DPN®) fabrication technique, Professor Zhang's group at Nanyang Technological University was able to directly deposit CoCl₂ onto graphene oxide sheets and subsequently catalyze carbon nanotubes in discrete localities. In a top-down nanofabrication application, Professor Bao's team at Stanford University harnessed DPN to fabricate electrical contacts on graphene and CNT devices without needing to expose the substrates to harsh e-beam irradiation.

Graphene

Graphene (and graphene oxide) has a unique two-dimensional structure, mechanical strength, electrical properties, and responsive surface chemistry which make it the ideal substrate for a wide variety of nanofabrication applications (including the construction of transistors and sensors) as well as for catalysis and drug delivery studies

With the ability to deposit materials to specific micro and nanoscale locations, DPN has emerged as a powerful tool for functionalizing graphene and for defining multiple local chemistries on other thin films in order to fabricate devices^{1, 2}. High resolution x, y stages coupled with the latest imaging systems and leading edge software enable NanoInk's DPN Systems (NSCRIPTOR™, DPN 5000, and NLP 2000) to achieve the high level of accuracy necessary for the functionalization of pre-fabricated microstructures like graphene.

In addition to playing an enabling role in the work of Professor Zhang^{3, 4} and Professor Bao⁵, DPN has been used by researchers in Professor Jang's laboratory to deposit two different materials and fabricate high mobility graphene nanoribbons (GNRs). Dr. Jang's team used a top-down polysterene-DPN technique for doing etch resists and a bottom-up gold nanoparticle-DPN process for electrode fabrication work⁶. At the United States Naval Research Laboratory, Professor Sheenan's group used thermal top-down DPN to fabricate masked, chemically isolated graphene nanoribbons⁷.

Want to learn even more about graphene applications using Dip Pen Nanolithography? Contact us! For information on other DPN applications see the Applications tab.

References

1. Krishnan, V., et al., Manipulation of thin film assemblies: Recent progress and novel concepts. Current Opinion in Colloid & Interface Science, 2011. 16(6): p. 459-469.
   
2. Zhou, X.Z., et al., Chemically Functionalized Surface Patterning. Small, 2011. 7(16): p. 2273-2289.
   
3. Li, B., et al., Controlled Assembly of Gold Nanoparticles and Graphene Oxide Sheets on Dip Pen Nanolithography-Generated Templates. Langmuir, 2009. 25(18): p. 10455-10458.
   
4. Li, H., et al., Single-layer graphene oxide sheet: a novel substrate for dip-pen nanolithography. Chemical Communications, 2011. 47(36): p. 10070-10072.
   
5. Wang, W.M., et al., Dip-Pen Nanolithography of Electrical Contacts to Single Graphene Flakes. ACS Nano, 2010. 4(11): p. 6409-6416.
   
6. Shin, Y.S., et al., High-Mobility Graphene Nanoribbons Prepared Using Polystyrene Dip-Pen Nanolithography. Journal of the American Chemical Society, 2011. 133(15): p. 5623-5625.
   
7. Lee, W.K., et al., Chemically Isolated Graphene Nanoribbons Reversibly Formed in Fluorographene Using Polymer Nanowire Masks. Nano Letters, 2011. 11(12): p. 5461-5464.
   

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