DC conductivity percolation on drying moistened mesoporous silica SBA-15

• Continuity of the residual surface water film in dehydrating SBA-15 is studied.
• DC conductivity percolation is used to monitor the continuity.
• The percolation exponent is found independent of the initial sample hydration.
• The percolation hydration threshold varied linearly with initial sample hydration.
• The failure of the conducting water network is connect by the substrate morphology.

DC conductivity percolation on drying to air in water-moistened SBA-15 was characterized. The percolation exponent value, μh ≈ 1, is typical for hydrophilic fumed silica and biological porous materials. Somewhat surprisingly, we found that the percolation water content threshold depends linearly of the initial hydration of dry SBA-15 material. The finding is rationalized within the concept of morphological wetting transition at hydrophilic/phobic structured interface of moistened SBA-15.

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