Electric conductivity percolation in naturally dehydrating, lightly wetted, hydrophilic fumed silica powder

Autor:	Bartosz Kieltyka, Jozef K. Moscicki, Daniel Dziob, Dagmara Sokolowska, Urszula Górska
Rok vydání:	2013
Předmět:	Condensed Matter::Soft Condensed Matter Materials science Electrical resistivity and conductivity Percolation Monolayer Analytical chemistry Ionic conductivity Percolation threshold Conductivity Condensed Matter::Disordered Systems and Neural Networks Grain size Fumed silica
Zdroj:	Physical Review E. 87
ISSN:	1550-2376 1539-3755
Popis:	In studying the dehydration of surface-moistened fumed silica Aerosil powders, we found a conductivity percolation transition at low hydration levels. Both the percolation exponent and the threshold are typical for correlated site-bond transitions in complex two-dimensional (2D) systems. The exponent values, 0.94--1.10, are indicative of severe heterogeneity in the conducting medium. The surface moisture at the percolation threshold takes on a universal value of 0.65 mg${}_{[\mathrm{H}2\mathrm{O}]}$/m${}^{2}$${}_{[\mathrm{silica}]}$, independent of the silica grain size, and equivalent to twice the first hydration monolayer. This level is just sufficient to sustain a quasi-2D, hydrogen-bonded water network spanning the silica surface.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_dedup___::e3955236db84c5166059a04515c8f689 https://doi.org/10.1103/physreve.87.062404 Zobrazit plný text záznamu