Long Zizhi, Chen Youzhi, Yin Weisong, Wu Xiuqi, Wang Yun
State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, Wuhan 430070, China.
Key Laboratory of Roadway Bridge & Structure Engineering, Wuhan University of Technology, Wuhan 430070, China.
Materials (Basel). 2022 Jun 14;15(12):4207. doi: 10.3390/ma15124207.
Despite their excellent performance, two-dimension nanomaterials have certain limitations in improving the performance of cement-based materials due to their poor dispersity in the alkaline environment. This paper has synthesized a new two-dimension stacked GO-SiO (GOS) hybrid through the sol-gel method. Nano-SiO is coated on the surface of GO with wrinkling characteristics, and the atomic ratio of C, O, and Si in GOS is 1:1.69:0.57. The paper discusses the impacts on the spreading, Marsh cone flow time, rheological properties, mechanical properties, and microstructure of cement-based materials for the GOS at different mixing quantities. Furthermore, with the same mixing quantity of 0.01%, the influences on the dispersity, flow properties, rheological parameters, and mechanical properties of GOS and graphene oxide (GO) are compared. Lastly, fuzzy matrix analysis has been adopted to analyze the comprehensive performance of cement-based materials containing GOS. The research results indicate that, compared with the reference sample, the spreading for the GOS cement mortar with 0.01% mixing quantity was reduced by 4.76%, the yield shear stress increased by 37.43%, and the equivalent plastic viscosity was elevated by 2.62%. In terms of the 28 d cement pastes, the compressive and flexural strength were boosted by 27.17% and 42.86%, respectively. According to the optical observation, GOS shows better dispersion stability in the saturated calcium hydroxide solution and simulated pore solution than GO. Compared with the cement-based materials with the same mixing quantity (0.01%), GOS has higher spreading, lower shear yield stress, and higher compressive and flexural strength than GO. Finally, according to the results of fuzzy matrix analysis, when the concentration of GOS is 0.01%, it presents a more excellent comprehensive performance with the highest score. Among the performance indicators, the most significant improvement was in the flexural properties of cement-based materials, which increased from 8.6 MPa to 12.3 MPa on the 28 d.
尽管二维纳米材料具有优异的性能，但由于它们在碱性环境中的分散性较差，在改善水泥基材料性能方面存在一定局限性。本文通过溶胶-凝胶法合成了一种新型的二维堆叠式氧化石墨烯-二氧化硅（GOS）复合材料。纳米二氧化硅包覆在具有褶皱特征的氧化石墨烯表面，GOS中C、O和Si的原子比为1:1.69:0.57。本文讨论了不同掺量的GOS对水泥基材料的扩展度、马氏漏斗流动时间、流变性能、力学性能和微观结构的影响。此外，在相同掺量0.01%的情况下，比较了GOS和氧化石墨烯（GO）对分散性、流动性能、流变参数和力学性能的影响。最后，采用模糊矩阵分析法对含GOS的水泥基材料的综合性能进行了分析。研究结果表明，与参考样品相比，掺量为0.01%的GOS水泥砂浆扩展度降低了4.76%，屈服剪应力提高了37.43%，等效塑性粘度提高了2.62%。对于28天龄期的水泥净浆，抗压强度和抗折强度分别提高了27.17%和42.86%。通过光学观察发现，GOS在饱和氢氧化钙溶液和模拟孔溶液中的分散稳定性优于GO。与相同掺量（0.01%）的水泥基材料相比，GOS具有更高的扩展度、更低的剪切屈服应力以及更高的抗压和抗折强度。最后，根据模糊矩阵分析结果，当GOS浓度为0.01%时，其综合性能表现更为优异，得分最高。在各项性能指标中，水泥基材料的抗折性能改善最为显著，28天时从8.6MPa提高到了12.3MPa。
