Zhang Z.-Q.,Jiangsu University |
Zhang Z.-Q.,Jiangsu Key Laboratory of Solar Materials |
Zhang Z.-Q.,Dalian University of Technology |
Ye H.-F.,Dalian University of Technology |
And 6 more authors.
Xinxing Tan Cailiao/New Carbon Materials | Year: 2013
The boundary slip and interfacial friction properties of confined-water flow on two parallel single-layer graphene sheets with a separation of 6 nm under electrowetting conditions were investigated by molecular dynamics simulation and boundary slip theory. For both electrowetted and uncharged graphenes, the flow velocity profiles perpendicular to the flow direction, shear stress, boundary slip velocity, slip length and interfacial friction coefficient were obtained with a graphene-water Couette flow model. Results show that the slip length increases abruptly when the shear rate is above a critical value. The critical shear rate in the electrowetted graphenes is obviously larger than that in uncharged ones. The interfacial friction coefficient between graphene and water decreases with the shear rate and is increased by electrowetting the graphenes. The water viscosity is independent of the shear rate in both eletrowetted and uncharged graphenes.
Ding J.N.,Changzhou University |
Ding J.N.,Jiangsu Key Laboratory of Solar Materials |
Liu Y.B.,Changzhou University |
Liu Y.B.,Jiangsu Key Laboratory of Solar Materials |
And 8 more authors.
Diamond and Related Materials | Year: 2012
The method of hydrothermal reduction was used to reduce graphite oxide (GO) and a series of experiments were made to investigate the influence of hydrothermal temperature, time and concentration on the reduction and dispersion effects. The atomic force Microscopy (AFM), UV/Vis spectroscopy (UV-vis), Fourier transform infrared (FTIR), X-ray diffraction (XRD), and thermogravimetric analysis (TGA) were used to confirm that the black suspension obtained in the critical conditions had been transformed into reduced graphene oxide (RGO). The as-prepared RGO can be dispersed in water forming suspensions with long-term stability without any organic solvents and other substances, which will facilitate the preparation of RGO-polymer composites and its applications. © 2011 Elsevier B.V. All rights reserved.