Abstract：The high concentration graphene aqueous dispersion was obtained by high-pressure homogenization liquid phase exfoliation (HPH-LPE) of flake graphite in water. The effect of surfactant concentration, HPH pressure and cycle number on the concentration of graphene dispersion CG was studied by UV-Vis spectra. The structure and morphology of graphene were analyzed by Roman spectra, SEM and TEM. The results indicate that CG is obtained up to 324.3mg·L-1 for the first time by the parameters optimization, which is 10 times higher than that obtained by sonication; graphene obtained has few defects, thin thickness and large size, indicating the good quality of graphene production; the conductivity of free-standing film prepared by the obtained graphene dispersion can reach 3.2×104S·m-1.
王晨, 燕绍九, 南文争, 王继贤, 彭思侃. 高浓度石墨烯水分散液的制备与表征[J]. 材料工程, 2019, 47(4): 56-63.
WANG Chen, YAN Shao-jiu, NAN Wen-zheng, WANG Ji-xian, PENG Si-kan. Preparation and characterization of high concentration graphene aqueous dispersion. Journal of Materials Engineering, 2019, 47(4): 56-63.
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