期刊
CONSTRUCTION AND BUILDING MATERIALS
卷 354, 期 -, 页码 -出版社
ELSEVIER SCI LTD
DOI: 10.1016/j.conbuildmat.2022.129121
关键词
Graphene oxide; Reduced graphene oxide; Durability; Microstructure
资金
- Guangdong Major Project of Basic and Applied Basic Research
- Innovative Model Factory Project of Songshan Lake Materials Labora-tory
- Basic Scientific Research Project of Education Department of Liaoning Province
- [2021B0301030002]
- [Y1D1051C511/Y1Q1011C511]
- [LJK20626]
- [LJKQZ2021144]
This study investigates the effect of reduced graphene oxides (rGO) with different oxygen concentrations on the durability and microstructure of cement-mortar composites. The results show that rGO with mild oxygen group level can significantly enhance the durability of the composites by reducing water absorption and promoting cement hydration reaction. The presence of mild oxygen acid groups on the surface of rGO acts as a neutralizer and improves the compactness of the matrix by forming calcium carbonate precipitation.
Graphene materials have been extensively explored and successfully used to improve the properties of cement -based composites. However, current studies mainly focus on optimizing additional amounts and dispersion modes of graphene. The influence of other parameters, such as graphene crystallinity, size, and oxygen -containing functional group level, on the performance of cement mortar composite is not fully understood. Therefore, in this study, a series of reduced graphene oxides (rGO) with different oxygen concentrations were synthesized by controlling two parameters, namely, different concentrations of L-Vitamin C (10, 20, 50, and 70 wt%) and different reduction times (15, 30, 45, and 60 min), and added to the cement-mortar composite at the same dosage. The effect of rGO with different oxygen concentrations on the durability and microstructure of the composites was investigated. The durability results revealed that rGO with mild oxygen group level (i.e., pre-pared by 50 % L-Vitamin C reduction for 30 min) can remarkably enhance the durability of cement mortar composite material. Adding 0.1 wt% rGO with mild oxygen concentration to the cement mortar caused the initial water absorption and secondary water absorption to decrease by 44.75 % and 31.95 %, respectively, compared with ordinary cement mortar. This enables rGO/cement-mortar composites to have outstanding resistance in harsh erosive environments (i.e., high concentrations of CO2) because rGO promotes the cement hydration re-action and generates more hydration products. Meanwhile, the mild oxygen acid groups on the surface of the rGO act as a neutralizer in a strong alkaline medium, resulting in the formation of calcium carbonate precipitation, which further improves the compactness of the matrix.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据