对浸入水或甲醇中的石墨氧化物的理论研究

采用密度泛函理论优化了含水和不含水的石墨氧化物的多种结构．当层间没有水分子时，优化的层间距在6A左右，小于6．5—7A的实验值．反之，含水石墨氧化物的层间距和实验值符合很好．基于优化的石墨氧化物结构，用分子动力学方法模拟了水或甲醇中的石墨氧化物．对于不含水的石墨氧化物，水和甲醇分子不进入其层间．而对于含水的石墨氧化物，液体分子进入层间，增大了层间距，半定量地重复了实验现象．

Theoretical Investigations on Graphite Oxide Immersed in Water or Methanol

Different structures of graphite oxide （GO） with and without water are optimized by density functional theory. Without H20 in interlayer space, the optimized interlayer distances are about 6A, smaller than the experimental values of 6.5-7A. On the other hand, the interlayer distances of hydrated graphite oxide structures are in good agreement with experimental observations. Based on the optimized GO structures, we then simulate the immersion of GO in water or methanol by molecular dynamics. For the dry GO, water and methanol molecules do not enter the nanopore. While for the hydrated GO, the liquid molecules enter the interlayer space and enlarge the interlayer distance, semi-quantitatively reproducing the experimental phenomena.