Qi Xiaoqiang, Zhang Sulei, Wang Tengteng, Guo Siyao, Ren Rui
Department of Civil Engineering, Qingdao University of Technology, Qingdao 266033, China.
Key Laboratory for Urban Underground Engineering of Ministry of Education, Beijing Jiaotong University, Beijing 100044, China.
Materials (Basel). 2021 Feb 15;14(4):915. doi: 10.3390/ma14040915.
Graphene's outstanding properties make it a potential material for reinforced cementitious composites. However, its shortcomings, such as easy agglomeration and poor dispersion, severely restrict its application in cementitious materials. In this paper, a highly dispersible graphene (TiO-RGO) with better dispersibility compared with graphene oxide (GO) is obtained through improvement of the graphene preparation method. In this study, both GO and TiO-RGO can improve the pore size distribution of cement mortars. According to the results of the mercury intrusion porosity (MIP) test, the porosity of cement mortar mixed with GO and TiO-RGO was reduced by 26% and 40%, respectively, relative to ordinary cement mortar specimens. However, the TiO-RGO cement mortars showed better pore size distribution and porosity than GO cement mortars. Comparative tests on the strength and durability of ordinary cement mortars, GO cement mortars, and TiO-RGO cement mortars were conducted, and it was found that with the same amount of TiO-RGO and GO, the TiO-RGO cement mortars have nearly twice the strength of GO cement mortars. In addition, it has far higher durability, such as impermeability and chloride ion penetration resistance, than GO cement mortars. These results indicate that TiO-RGO prepared by titanium dioxide (TiO) intercalation can better improve the strength and durability performance of cement mortars compared to GO.
石墨烯优异的性能使其成为增强水泥基复合材料的潜在材料。然而,其缺点,如易团聚和分散性差,严重限制了其在水泥基材料中的应用。本文通过改进石墨烯制备方法,获得了一种与氧化石墨烯(GO)相比具有更好分散性的高分散性石墨烯(TiO-RGO)。在本研究中,GO和TiO-RGO均能改善水泥砂浆的孔径分布。根据压汞法(MIP)测试结果,与普通水泥砂浆试件相比,掺GO和TiO-RGO的水泥砂浆孔隙率分别降低了26%和40%。然而,TiO-RGO水泥砂浆比GO水泥砂浆表现出更好的孔径分布和孔隙率。对普通水泥砂浆、GO水泥砂浆和TiO-RGO水泥砂浆的强度和耐久性进行了对比试验,发现相同用量的TiO-RGO和GO,TiO-RGO水泥砂浆的强度几乎是GO水泥砂浆的两倍。此外,它具有比GO水泥砂浆更高的耐久性,如抗渗性和抗氯离子渗透性。这些结果表明,与GO相比,通过二氧化钛(TiO)插层制备的TiO-RGO能更好地改善水泥砂浆的强度和耐久性性能。