中国物理B ›› 2015, Vol. 24 ›› Issue (10): 108201-108201.doi: 10.1088/1674-1056/24/10/108201
• INTERDISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY • 上一篇 下一篇
裘英华, 李堃, 陈伟宇, 司伟, 谭启檐, 陈云飞
Qiu Ying-Hua (裘英华), Li Kun (李堃), Chen Wei-Yu (陈伟宇), Si Wei (司伟), Tan Qi-Yan (谭启檐), Chen Yun-Fei (陈云飞)
摘要: Porous graphene has a high mechanical strength and an atomic-layer thickness that makes it a promising material for material separation and biomolecule sensing. Electrostatic interactions between charges in aqueous solutions are a type of strong long-range interaction that may greatly influence fluid transport through nanopores. In this study, molecular dynamic simulations were conducted to investigate ion and water transport through 1.05-nm diameter monolayer graphene nanopores, with their edges charge-modified. Our results indicated that these nanopores are selective to counterions when they are charged. As the charge amount increases, the total ionic currents show an increase-decrease profile while the co-ion currents monotonically decrease. The co-ion rejection can reach 76.5% and 90.2% when the nanopores are negatively and positively charged, respectively. The Cl- ion current increases and reaches a plateau, and the Na+ current decreases as the charge amount increases in systems in which Na+ ions act as counterions. In addition, charge modification can enhance water transport through nanopores. This is mainly due to the ion selectivity of the nanopores. Notably, positive charges on the pore edges facilitate water transport much more strongly than negative charges.
中图分类号: (Computational modeling; simulation)