氧化石墨烯尺寸对水泥基复合材料的影响

Effect of Graphene Oxide Size on Cement-Based Composites

采用Hummers法以石墨粉为原料制备氧化石墨烯(GO),采用球磨法制备不同尺寸的氧化石墨烯纳米片,分别使用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、透射电镜(TEM)和马尔文激光粒度仪(Zetasizer Nano,ZS)进行结构表征。结果表明,球磨法可制备不同粒径分布的氧化石墨烯纳米片;水泥基复合材料的SEM微观形貌以及力学性能测定结果显示当掺杂0.25%、球磨16 h制得的氧化石墨烯(80~184 nm),复合材料的抗折、抗压强度分别为12.1 MPa和73 MPa,相较于对照样品提高了47.56%和38.52%;小尺寸氧化石墨烯促进水泥内部形成规则有序的水化物,这些水化物在水泥内堆叠,形成相互交联的晶体网络,微观上改变复合材料内部结构,宏观上提高了其力学性能。

Graphene oxide(GO) was prepared by Hummers method with graphite powder as raw material.Different size of GO was synthesized by ball milling method.The structure and surface morphology of GO was characterized by X-ray diffraction(XRD),scanning electron microscope(SEM),transmission electron microscope(TEM) and laser particle size analyzer(Zatasizer Nano,ZS).The results indicate that GO with different particle size can be prepared by ball milling method.The results of SEM images and mechanical strength show that 0.25% of GO(ball milling for 16 h,80-184 nm) is doped into the composites,the flexural and compressive strength of the composites are 12.1 MPa and 73 MPa,respectively,which increase by 47.56% and 38.52% compared to the control sample.The small size of GO promotes the formation of regular and orderly hydrates that stacked in the cement matrix and formed an interwoven crystal network,which changes the internal microstructure and improves its mechanical properties.