Felix Bloch Institute for Solid State Physics, University of Leipzig, Leipzig, Germany.
Sci Rep. 2017 Aug 3;7(1):7216. doi: 10.1038/s41598-017-07406-2.
Fluids confined in mesoporous solids exhibit a wide range of physical behavior including rich phase equilibria. While a notable progress in their understanding has been achieved for fluids in materials with geometrically ordered pore systems, mesoporous solids with complex pore geometries still remain a topic of active research. In this work we study phase transitions occurring in statistically disordered linear chains of pores with different pore sizes. By considering, quite generally, two phase change mechanisms, nucleation and phase growth, occurring simultaneously we obtain the boundary transitions and the scanning curves resulting upon reversing the sign of the evolution of the chemical potential at different points along the main transition branches. The results obtained are found to reproduces the key experimental observations, including the emergence of hysteresis and the scanning behavior. By deriving the serial pore model isotherm we suggest a robust framework for reliable structural analysis of disordered mesoporous solids.
在中孔固体中受限的流体表现出广泛的物理行为，包括丰富的相平衡。虽然对于具有几何有序孔系统的材料中的流体，已经在其理解方面取得了显著进展，但具有复杂孔几何形状的中孔固体仍然是一个活跃的研究课题。在这项工作中，我们研究了在具有不同孔径的统计无序线性孔链中发生的相转变。通过相当普遍地考虑同时发生的两种相转变机制，成核和相生长，我们得到了边界转变和在沿着主转变分支的不同点反转化学势演化的符号时得到的扫描曲线。所得到的结果被发现再现了关键的实验观察结果，包括滞后和扫描行为的出现。通过推导出串联孔模型等温线，我们为无序中孔固体的可靠结构分析提出了一个稳健的框架。
