物理化学学报 >> 2015, Vol. 31 >> Issue (8): 1499-1503.doi: 10.3866/PKU.WHXB201506191

理论与计算化学 上一篇    下一篇

平衡时溶液的表面吸附

陈飞武*(),卢天,武钊   

  1. 1 北京科技大学化学与生物工程学院化学与化学工程系,北京100083
    2 功能分子与晶态材料科学与应用北京市重点实验室,北京100083
  • 收稿日期:2015-03-04 发布日期:2015-08-12
  • 通讯作者: 陈飞武 E-mail:chenfeiwu@ustb.edu.cn
  • 基金资助:
    国家自然科学基金(21173020);国家自然科学基金(21473008)

Surface Absorption of a Solution at Equilibrium

Fei-Wu. CHEN*(),Tian. LU,Zhao. WU   

  1. 1 Department of Chemistry and Chemical Engineering, School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing 100083, P. R. China
    2 Beijing Key Laboratory for Science and Application of Functional Molecular and Crystalline Materials, Beijing 100083, P. R. China
  • Received:2015-03-04 Published:2015-08-12
  • Contact: Fei-Wu. CHEN E-mail:chenfeiwu@ustb.edu.cn
  • Supported by:
    the National Natural Science Foundation of China(21173020);the National Natural Science Foundation of China(21473008)

摘要:

溶液的表面吸附仍是表面热力学当中的一个具有挑战性的问题.在本文中我们定义了一个新的热力学态函数,表面吸附的平衡条件是这个态函数的微分为零.基于这个条件,我们推导了描述平衡时表面吸附的新方程.在推导过程中没有采用假想分界面.新的表面吸附方程和Gibbs表面吸附方程完全不一样.还通过分子动力学方法模拟了氯化钠溶液,模拟结果和我们的理论预测符合较好.

关键词: 表面吸附, 平衡条件, 吉布斯吸附方程, 热力学态函数, 溶液

Abstract:

Surface adsorption of a solution is still a challenging problem in the thermodynamics of surfaces. In this work, a new thermodynamic state function is defined. The equilibrium condition of surface adsorption is that the differential of this state function is equal to zero. Based on this condition, we derived a new equation to describe surface adsorption at equilibrium. No hypothetical dividing surface is needed in this derivation. The new equation is quite different from the Gibbs adsorption equation. We also performed molecular dynamic simulations of aqueous sodium chloride solutions. The simulated results are in good agreement with our theoretical predictions.

Key words: Surface absorption, Equilibrium condition, Gibbs absorption equation, Thermodynamic state function, Solution