High-pressure effect in ionically conducting nanostructured silicates

Abstract

Silver orthosilicate shells with a thickness around 21 nm were grown around silver nanoparticles of diameter ~20 nm within a silicate glass matrix. The resistivity variation as a function of temperature in the range 300 to 625 K showed an activated behavior usual for an ionic conductor but with discontinuous changes at certain temperatures. The nature of resistivity decrease leads us to believe that this behavior arises due to excitation of quantized acoustic modes whenever the circumference length of the nanoshell changes by an amount equivalent to Si-O distance on deformation under high pressure. The vibrational frequencies as extracted from the experimental data are in reasonable agreement with the quantized mode frequencies predicted by Lamb's theory.