Abyzov Alexander S, Davydov Leonid N, Schmelzer Jürn W P
National Science Center Kharkov Institute of Physics and Technology, 61108 Kharkov, Ukraine.
Institute of Physics, University of Rostock, Albert-Einstein-Strasse 23-25, 18059 Rostock, Germany.
Entropy (Basel). 2019 Aug 9;21(8):782. doi: 10.3390/e21080782.
Heterogeneous nucleation of new phase clusters on a rough solid surface is studied. The ambient phase is considered to be a regular supersaturated solution. In contrast to existing studies of the same problem, the possible difference between the state parameters of the critical cluster and the corresponding parameters of a newly formed macroscopic phase is accounted for. This account is performed within the framework of the generalized Gibbs approach. Surface imperfections are chosen in the form of cones. The model allows us to simplify the analysis but also to obtain the basic results concerning the defect influence on the nucleation process. It is shown that the catalytic activity factor for nucleation of the cone depends both on the cone angle and the supersaturation in the solution determining the state parameters of the critical clusters. Both factors considerably affect the work of critical cluster formation. In addition, they may even lead to a shift of the spinodal curve. In particular, in the case of good wettability (macroscopic contact angle is less than 90°) the presence of surface imperfections results in a significant shifting of the spinodal towards lower values of the supersaturation as compared with heterogeneous nucleation on a planar solid surface. With the decrease of the cone pore angle, the heterogeneous spinodal is located nearer to the binodal, and the metastability range is narrowed, increasing the range of states where the solution is thermodynamically unstable.
研究了粗糙固体表面上新相簇的非均匀成核。周围相被视为常规过饱和溶液。与相同问题的现有研究不同，考虑了临界簇的状态参数与新形成的宏观相的相应参数之间可能存在的差异。这种考虑是在广义吉布斯方法的框架内进行的。表面缺陷采用圆锥体的形式。该模型不仅使我们能够简化分析，还能获得有关缺陷对成核过程影响的基本结果。结果表明，圆锥体成核的催化活性因子既取决于圆锥角，也取决于溶液中的过饱和度，而过饱和度决定了临界簇的状态参数。这两个因素都对临界簇形成的功有显著影响。此外，它们甚至可能导致亚稳线的移动。特别是，在润湿性良好（宏观接触角小于90°）的情况下，与平面固体表面上的非均匀成核相比，表面缺陷的存在会导致亚稳线显著向较低的过饱和度值移动。随着圆锥孔角的减小，非均匀亚稳线更靠近双节线，亚稳范围变窄，增加了溶液热力学不稳定的状态范围。
