Electrokinetic characteristics of initial porous glasses and those modified with titanium- and aluminum-oxide particles

Abstract

The structural (volume porosity, structural resistance coefficient, and average pore radius) and electrokinetic (specific electrical conductivity, ion-transport numbers, and electrokinetic potential) characteristics of macroporous glass membranes obtained from two-phase sodium-borosilicate glasses with different times of thermal treatment have been studied in solutions of hydrochloric acid and potassium chloride. The properties of the initial membranes have been compared with the characteristics of the same membranes modified by filtering through them suspensions of aluminum- and titanium-oxide nanoparticles with different weight concentrations. It has been shown that, at low degrees of pore channel surface coverage with nanoparticles (<0.1), the structural parameters of the membranes remain almost unchanged. In addition, it has been found that the presence of positively charged nanoparticles on the negatively charged surface increases the surface conductivity and the absolute value of the electrokinetic potential.