The results of investigations of porous glasses (PG) and porous glasses–ammonium hydrogen sulfate ferroelectric nanocomposites (AHS–PG) are presented. On the basis of dielectric and calorimetric measurements it was shown that in the AHS–PG nanocomposites with average pore size of 44, 68, 95, and 320 nm the anomalies of dielectric permittivity and specific heat similar to those in bulk crystals AHS are observed. An influence of the mean value of pores sizes on the ferroelectric phase transition temperatures of AHS nanocrystals embedded into the porous matrices was determined. It was shown that in AHS–PG dispersion of the dielectric permittivity is observed in both para- and ferro-electric phases and above room temperature AHS–PG nanocomposites exhibit the ionic conductivity.

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Porous glasses with an aligned pore system were prepared by using a stretch-forming device. For the experiments a sodium borosilicate glass with the composition 62.5 wt% SiO 2 , 30.5 wt% B 2 O 3 and 7 wt% Na 2 O was prepared. The characterization of this glass includes X-ray fluorescence analysis and dilatometry. The applied stretch-forming apparatus allowed the simultaneous phase separation and elongation of the glass samples. The obtained glass templates were chemically treated with hydrochloric acid and sodium hydroxide solution to extract the soluble sodium rich borate phase. The resulting porous glass samples were characterized by environmental scanning electron microscopy and mercury intrusion. Different degrees of pore alignment were realized by varying the parameters of the stretch-forming process.

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