高浓度石墨烯水分散液的制备与表征

利用高压均质液相剥离法,以鳞片石墨为原料,水为介质,制备高浓度石墨烯水分散液。采用紫外可见光谱研究表明活性剂浓度、高压均质压力和循环次数对石墨烯水分散液浓度C_G的影响。通过拉曼光谱、扫描电镜、透射电镜、激光粒度仪分析水分散液中石墨烯的结构和形貌。结果表明:通过调节各工艺参数,获得了浓度为324.3mg·L^-1的石墨烯水分散液,所得浓度是超声液相剥离法的10倍;石墨烯水分散液中石墨烯缺陷少、厚度薄、片径大,具有良好的品质;将所得石墨烯分散液制备石墨烯自支撑膜,其电导率可达3.2×10~4S·m^-1。

Preparation and characterization of high concentration graphene aqueous dispersion

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 3.2×10^4S·m^-1.