Understanding capillary condensation and hysteresis in porous silicon: network effects within independent pores.
Understanding capillary condensation and hysteresis in porous silicon: network effects within independent pores.
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了解多孔硅中的毛细管冷凝和滞后：独立孔隙内的网络效应。
DOI：
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发表时间：
2008
期刊：
影响因子：
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通讯作者：
P. A. Monson
中科院分区：
文献类型：
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作者：
S. Naumov;A. Khokhlov;R. Valiullin;J. Kärger;P. A. Monson
多孔硅材料具有很大程度的孔隙结构控制能力，这使得多孔硅材料成为研究孔隙结构、毛细凝结和滞后现象之间关系的理想材料。利用实验测量和平均场理论中的晶格气体模型，研究了孔隙尺寸不均匀性和表面粗糙度对具有线性孔隙的多孔硅中氮气在77K时毛细凝聚的影响。我们的结果解决了早期实验工作的一些令人困惑的特点。我们发现这种材料与Vycor玻璃等无序材料有更多的共同之处，而不是经典吸附文献中讨论的理想的光滑壁圆柱形孔隙。我们提供了强有力的证据表明，这种行为来自于独立线性孔隙内部过程的复杂性，这是由于孔隙大小沿孔轴的不均匀性引起的，而不是不同孔隙之间的协同效应。
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.