Spinodal Decomposition by a Two-Step Procedure for Nano Porous Silica.

ABSTRACT: The phase separation of the Na₂O-B₂O₃-SiO₂ system was explored both theoretically and experimentally in order to attain a spinodal structure having a narrowed periodic distance (<70 nm) with the porosity being kept at ∼60%. The phase separation was dealt with by two stages: an initial thermodynamic process of spinodal decomposition and a latter growth of the spinodal structure. The initial structural development was related to the interfacial energy and the change in free energy caused by phase separation. For the latter growth, a mathematical model was proposed to explain the kinetics by incorporating the effect of the inverse-square law in the diffusion of SiO₂, and a basic relation of (d: average periodic distance; t:

SUBMITTER: Zhang Z 

PROVIDER: S-EPMC11613344 | biostudies-literature | 2024 Nov

REPOSITORIES: biostudies-literature