第一个原则是研究用功能化石墨烯氧化物修改的水泥砂的机械性能
Lin Wei1, GuiLi Liu2, JiaXin Wang1
1College of Architecture and Civil Engineering, Shenyang University of Technology, No. 111 Shenliao West Road, Economic and Technological Development District, Shenyang, 110870, Liaoning, China.
Journal of molecular modeling
|November 6, 2023
概括
石墨烯上的功能组显著增强了石墨烯-水泥复合材料的机械性能和界面粘合. 这改善了电荷传输,并加强了材料的整体性能.
科学领域:
- 材料科学 材料科学 材料科学
- 计算化学计算化学
- 土木工程 土木工程是指土木工程.
背景情况:
- 原始石墨烯-水泥接口 (G/C-S-H) 的剪切强度为12 MPa.
- 功能化石墨烯接口 (G-O/C-S-H,G-OH/C-S-H,G-COOH/C-S-H) 的剪切强度分别为21 MPa,29 MPa和14 MPa.
- 石墨烯上的功能组改变了电子分布,增强了界面相互作用,促进了化学键的形成.
研究的目的:
- 研究功能组对石墨烯-水泥接口的机械和电气性能的影响.
- 阐明改善界面强度和电荷转移背后的机制.
- 为优化石墨烯增强水泥材料提供见解.
主要方法:
- 使用材料工作室中的CASTEP模块进行第一原则计算.
- 使用GGA-PBE函数的几何优化.
- 对于自相一致场 (2.0 × 10−6 eV) 和结构优化 (0.02 eV/Å) 的具体收标准.
主要成果:
- 与原始石墨烯相比,功能组显著提高了石墨烯-水泥接口的剪切强度.
- 吸附的功能组改变了石墨烯表面的电子分布.
- 石墨烯-水泥接口充当桥梁,增强电荷转移和固体化学键生成.
结论:
- 引入功能组对于增强石墨烯-水泥接口的机械性能至关重要.
- 功能化促进了更强的相互作用和更好的电荷传输,从而提高了复合材料的性能.
- 这些发现为设计具有卓越机械和电气性能的先进水泥复合材料提供了途径.
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