AAAR 34th Annual Conference
October 12 - October 16, 2015
Hyatt Regency
Minneapolis, Minnesota, USA
Abstract View
Mobility and Charging Characteristics of Crumpled Reduced Graphene Oxide Synthesized by Aerosol Process
YAO NIE, Yang Wang, Yi Jiang, Pratim Biswas, Washington University in St. Louis
Abstract Number: 352 Working Group: Nanoparticles and Materials Synthesis
Abstract Graphene nanosheets, with their excellent electronic conductivity and extremely large specific surface area, have recently attracted great interest. Aerosol process of converting the flat 2D structure to a 3D crumpled one has broadened the application of graphene materials by overcoming the restacking of these nanosheets.[1] In this study, crumpled graphene oxide (C-GO) was synthesized using a furnace aerosol reactor (FuAR) in which graphene oxide was thermally reduced. By using a differential mobility analyzer (DMA), C-GO nanoparticles of uniform mobility sizes were classified and collected. The morphology and sizes of these C-GO nanoparticles were characterized by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The projection size of C-GO calculated from offline measurements was correlated to the electrical mobility size of C-GO measured by a DMA. Due to the unique crumpled structure of C-GO, the projection size deviated from the electrical mobility size. In addition, the effects of morphology (flat, wrinkled, or crumpled) on the mobility size were compared. Further, the bipolar diffusion charging characteristics of C-GO synthesized with different temperatures were studied with a tandem DMA system, from which the multiply charged fraction of C-GO could be determined. The neutral fraction of C-GO was thus calculated by considering the multiply charged fraction. The synthesis temperature significantly affected the neutral fraction of C-GO with the same mobility, which may be attributed to the different conductivities of C-GO (thermally) reduced at different temperatures. The correlation between the electrical capacitance deduced from the neutral fraction and the conductivity of C-GO will be discussed in this work.
[1] Wang, W.-N.; Jiang, Y.; Biswas, P. Evaporation-Induced Crumpling of Graphene Oxide Nanosheets in Aerosolized Droplets: Confinement Force Relationship. The Journal of Physical Chemistry Letters 2012, 3, 3228-3233.