Phase Transition in Potassium Nitrate Ferroelectric in a Nanoporous Matrix

Differential scanning calorimetry has been used to carry out a precision study of KNO3 introduced into a silicate nanoporous matrix. Heat capacity peaks associated with ferroelectric phase transitions were found and examined. The characteristics of these transitions were examined in terms of the theory of diffuse phase transitions. A hypothesis was made that there exists a minimum size of pores in the nanocomposite at which KNO3 is in the fully ferroelectric state at room temperature.