AVS 63rd International Symposium & Exhibition
    2D Materials Focus Topic Thursday Sessions
       Session 2D-ThP

Paper 2D-ThP2
Inkjet Printing Of Liquid-Exfoliated, Highly Conducting Graphene Nanosheets

Thursday, November 10, 2016, 6:00 pm, Room Hall D

Session: 2D Materials Poster Session
Presenter: Jorge Catalan, University of Texas at El Paso
Authors: J. Desai, University of Texas at El Paso
M. Michel, University of Texas at El Paso
C. Biswas, University of Texas at El Paso
R. Hossain, University of Texas at El Paso
J. Catalan, University of Texas at El Paso
A.B. Kaul, University of Texas at El Paso
Correspondent: Click to Email
Graphene consisting of just one sheet of carbon atoms arranged in a honeycomb lattice is a thinnest two-dimensional (2-D) material known since its discovery in 2004. It finds applications in printed electronics, flexible displays, fuel cells, solar cells and range of other applications due to its high strength and good thermal and electrical properties. Two-dimensional materials are formed from layered materials which can be defined as materials having strong in-plane covalent bonding but weak out-of-plane van der Waals bonding. Exfoliation, i.e., shearing of individual monolayers of layered materials to get two-dimensional materials, can lead to breakage of van der Waals bonding and production of thin atomic two-dimensional nanosheets. Liquid-phase exfoliation refers to exfoliation in suitable solvents. It is a versatile, scalable and sustainable route for production of 2-D nanosheets. Inkjet printing is a material-conserving deposition technique used for printing patterns and devices using liquid-phase materials. The present challenges in printed electronics include finding an appropriate common solvent for exfoliation and printing, printing highly conductive and uniform graphene patterns, preventing nozzle clogging and non-uniform spread of ink on substrate, promoting adsorption and preventing absorption of inks. In our work, we demonstrate highly conductive graphene patterns produced by liquid-phase exfoliation of layered graphite in N-Methyl-2-pyrrolidone (NMP) followed by inkjet printing. We have found an avenue to tailor the viscosity of NMP though the addition of PEDOT: PSS or Poly (3,4 ethylenedioxythiophene)-poly(styrenesulfonate), making it suitable for inkjet printing.. Our ink jet printed dispersions show a uniform microstructure, good optical absorbance values and higher concentration of graphene in our final exfoliated solvent using the novel techniques we have developed.