Dielectric properties of mixed NaNO2-KNO3 ferroelectrics in nanoporous silicate matrices

Results of dielectric studies of MCM-41 molecular sieves with mesoporous channels (37.0 and 24.3 Å in size) loaded with the ferroelectric (NaNO2)1 − x (KNO3) x (x = 0, 0.05, 0.10) are presented. The experimental data on the permittivity and conductivity of the composite are used to calculate the temperature dependences of the permittivity and conductivity of these solid solutions in pores. The permittivity and conductivity are found to increase with increasing KNO3 concentration both in bulk samples and under restricted geometry conditions. An increase in the permittivity and conductivity due to the restricted geometry as compared to bulk mixtures was found to occur for all values of x. The mechanisms underlying this behavior are discussed.