Naumov Sergej, Khokhlov Alexey, Valiullin Rustem, Kärger Jörg, Monson Peter A
Department of Interface Physics, University of Leipzig, D-04103 Leipzig, Germany.
Phys Rev E Stat Nonlin Soft Matter Phys. 2008 Dec;78(6 Pt 1):060601. doi: 10.1103/PhysRevE.78.060601. Epub 2008 Dec 1.
The ability to exert a significant degree of pore structure control in porous silicon materials has made them attractive materials for the experimental investigation of the relationship between pore structure, capillary condensation, and hysteresis phenomena. Using both experimental measurements and a lattice gas model in mean field theory, we have investigated the role of pore size inhomogeneities and surface roughness on capillary condensation of N2 at 77K in porous silicon with linear pores. Our results resolve some puzzling features of earlier experimental work. We find that this material has more in common with disordered materials such as Vycor glass than the idealized smooth-walled cylindrical pores discussed in the classical adsorption literature. We provide strong evidence that this behavior comes from the complexity of the processes within independent linear pores, arising from the pore size inhomogeneities along the pore axis, rather than from cooperative effects between different pores.
在多孔硅材料中实现对孔隙结构的显著控制能力，使其成为研究孔隙结构、毛细凝聚和滞后现象之间关系的实验研究的有吸引力的材料。通过实验测量和平均场理论中的晶格气体模型，我们研究了孔径不均匀性和表面粗糙度对77K下氮气在具有线性孔隙的多孔硅中的毛细凝聚的作用。我们的结果解决了早期实验工作中的一些令人困惑的特征。我们发现，这种材料与诸如Vycor玻璃等无序材料有更多共同之处，而不是经典吸附文献中讨论的理想化光滑壁圆柱形孔隙。我们提供了有力证据，表明这种行为源于独立线性孔隙内过程的复杂性，这是由沿孔隙轴的孔径不均匀性引起的，而不是来自不同孔隙之间的协同效应。
