Electrorheological Effects of Cerium-Doped TiO_(2)

It is found that doping of cerium ion into anatase TiO_(2)can improve the electrorheological(ER)effects of TiO_(2)and broaden operational temperature range.Especially,substitution of 7-11mol%of the cerium dopant for Ti can obtain a relatively high shear stress,τ=7.4kPa(at 4kV/mm),which is ten times larger than that of pure TiO_(2)ER fluid.Also,the typical Ce-doped TiO_(2)ER fluid shows the highest shear stress at 80℃,but 40℃for pure TiO_(2)ER fluid.The dielectric loss and dielectric constant at low frequency of TiO_(2)is improved by the doping of cerium,and the temperature dependence of the dielectric properties shows an obvious difference between pure and doped TiO_(2)ER fluid.These can well explain the ER behaviour of doped TiO_(2).Furthermore,the change of rheological and dielectric properties is discussed on the basis of the lattice distortion and defects in TiO_(2)arising from the doping of cerium.