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  • Exfoliation and Spray Deposition of Graphene Nanoplatelets in Ethyl Acetate and Acetone: Implications for Additive Manufacturing of Low-Cost Electrodes and Heat Sinks
Title: Exfoliation and Spray Deposition of Graphene Nanoplatelets in Ethyl Acetate and Acetone: Implications for Additive Manufacturing of Low-Cost Electrodes and Heat Sinks
Nonaqueous dispersions of graphene nanoplatelets (GrNPs) can be used to prepare thin films and coatings free of surfactants, but typically involve polar organic solvents with high boiling points and low exposure limits. Here we describe the mechanochemical exfoliation and dispersion of GrNPs in volatile aprotic solvents such as ethyl acetate (EtOAc) and acetone, which rank favorably in green solvent selection guides. GrNPs in powder form were exfoliated with solvent on a horizontal ball mill for 48 hours then sonicated at moderate power, to produce suspensions in excess of 300 µg/mL with minimum loss of dispersion stability over 7 weeks at room temperature. Atomic force microscopy (AFM) of individual particles indicate a median thickness and lateral width of 8‒10 layers and 180 nm, respectively. GrNP films can be deposited by conventional airbrush equipment with a dry time of seconds and applied as layers and coatings that enhance the reproducibility and performance of electronic devices. We demonstrate the utility of spray-coated GrNPs as contact layers for low-cost electrochemical sensing with improvements in intrabatch reproducibility, and as conformal coatings on metal heat sinks with enhanced rates of heat dissipation.  more » « less
Award ID(s):
2204206 2016453
PAR ID:
10506699
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
American Chemical Society
Date Published:
Journal Name:
ACS Applied Nano Materials
Volume:
6
Issue:
15
ISSN:
2574-0970
Page Range / eLocation ID:
14574 to 14582
Subject(s) / Keyword(s):
graphene liquid-phase exfoliation electrochemical sensors heat exchange nanomanufacturing
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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