Lyotropic liquid crystals have lubricating properties due to their ordered assembly and fluidity, whose mesogens are often characterized by amphiphilic properties. Despite the attention that graphene oxide (GO) has been studied as a novel amphiphilic lyotropic mesogen this decade, and GO applied as a lubrication additive has been demonstrated in both oil and water-based systems, little research reveals the interfacial lubrication of GO liquid crystals yet. This work reports that GO aqueous dispersion can form lyotropic liquid crystals above a specific critical concentration of 5.00 mg/mL, providing a form of stable water-based lubricant, which can keep stable for several months and can reduce friction by 37.3% and wear by 25.24%. The liquid crystal phase was verified by polarizing microscope and synchrotron radiation small-angle X-ray scattering, and its rheological properties and viscoelasticity were studied by interfacial rheometer. The formation of lyotropic liquid crystals can enhance the stability of GO aqueous dispersions at high density, simultaneously ensuring friction decrease and anti-wear effect. It is attributed to the stable nematic network by the ordered GO sheets. The ordered assembly structure bears vertical shear force, therefore, reducing the wear. It is also assumed that the wide lateral size of graphene oxide promotes the nematic phase thus smoothes the graphene oxide film composed spontaneously under the coincidence of lamellar liquid crystal and 2D layered material. Through this work, the interlayer lubrication of GO was optimized, and the problem of GO dispersion sedimentation was solved by self-assembly. The range of interfacial lubrication of GO aqueous dispersion has been expanded and the synergistic effect is conducive to the environmentally friendly lubricants.

溶致液晶由于其有序组装和流动性而具有润滑性能，其介晶通常具有两亲性。尽管近十年来，氧化石墨烯（GO）作为一种新型两亲性溶致介晶受到关注，并且GO作为润滑添加剂的应用已在油基和水基体系中得到证实，但很少有研究揭示GO液晶的界面润滑作用然而。该工作报告称，GO水分散体在特定临界浓度5.00 mg/mL以上可形成溶致液晶，提供一种稳定的水基润滑剂，可保持稳定数月，并可减少37.3%的摩擦和磨损25.24%。通过偏光显微镜和同步辐射小角X射线散射验证了液晶相，并通过界面流变仪研究了其流变性能和粘弹性。溶致液晶的形成可以增强GO水分散体在高密度下的稳定性，同时保证减摩和抗磨效果。这归因于有序 GO 片形成的稳定向列网络。有序的装配结构承受垂直剪切力，减少磨损。还假设氧化石墨烯的宽横向尺寸促进了向列相，从而使在层状液晶和二维层状材料的重合下自发组成的氧化石墨烯膜变得平滑。通过这项工作，优化了GO的层间润滑，并通过自组装解决了GO分散沉降的问题。 GO水分散体的界面润滑范围扩大，协同效应有利于环保型润滑油。