An enhanced polarization mechanism for the metal cations modified amorphous TiO2 based electrorheological materials.

In the present work, we developed a new kind of electrorheological (ER) materials, metal cations modified amorphous TiO(2) gels. The static yield stress of Sn(4+) modified amorphous TiO(2) gel based ER fluid with a volume fraction Phi = 38% reaches 26.2 kPa at E = 3.5 kV/mm. The result shows that metal cations can significantly enhance the ER activity of amorphous TiO(2) gels. We then proposed a novel ER effect mechanism (metal cations enhanced polarization mechanism) to clarify the experimental results. We believe that it is the metal cations that enhanced the polarization of the polar groups (-OH) which results in the corresponding enhancement of the interfacial polarization.