石墨烯及氧化石墨烯对水泥基材料水化过程及强度的影响

Effect of Graphene and Graphene Oxide on Hydration Process and Strength of Cement-based Materials

本工作采用超声分散方法将插层剥离法制备的石墨烯pG(Peeling graphene)及传统Hummers法制备的氧化石墨烯hGO(Hummers graphene oxide)制备成纳米片分散液,研究了两种分散液对水泥基材料凝结时间、水化产物微观结构及强度的影响。结果表明:两种纳米片分散液的掺入均能明显缩短水泥的凝结时间,减少水泥石内部的孔隙,使结构致密化,部分CH晶体呈现出由一位点向外发散的多面聚集的结构状态。pG和hGO的加入能加速水泥水化反应速率,未改变水化产物的种类,还可提高水泥基材料的力学性能,尤其是3 d抗折强度提高最为明显。掺pG的试件均比掺hGO的试件强度略高,这为成本低、尺寸可控、可批量生产的石墨烯产品在水泥基材料中的应用提供了广阔的应用前景。

In this work,peeling graphene(pG)prepared by intercalation stripping method and Hummers graphene oxide(hGO)prepared by Hummers method were prepared into nano sheet dispersion by ultrasonic dispersion method.The effects of two kinds of dispersions on setting time,microstructure of hydration products,crystalline phase and strength of cement-based materials were studied.The results show that the mixing of two nano dispersions can shorten the setting time reduce the pores in the cement paste,and densify the structure,and some CH crystal present a multi-faceted aggregation structure state that diverges from a single point.The addition of pG and hGO can accelerate the hydration reaction of cement,do not change the types of hydration products,and can improve the mechanical properties of cement-based materials,especially the 3 d flexural strength.The strength of cement sample with pG is slightly higher than that of hGO,which provides a broad prospect for the application of low-cost,size-controllable and mass-produced graphene products in cement-based materials.