Study of wet mesostructure silica MCM-41 by low frequency dielectric spectroscopy

TL;DR

This study investigates the dielectric properties of wet mesostructured silica MCM-41 across a broad frequency and temperature range, revealing a phase transition near -40°C and evidence of liquid crystal and ferroelectric phases.

Contribution

It provides new insights into the low-frequency dielectric behavior and phase transitions of wet mesostructured silica MCM-41, including the identification of ferroelectric phases.

Findings

Phase transition near -40°C observed.

Existence of liquid crystal state at higher temperatures.

Presence of ferroelectric phase at lower temperatures.

Abstract

The dielectric measurements of mesostructured silica MCM-41 with the pore diameter 3.5 nm at wettings close to maximal were carried out. The measurements were made by using the dielectric spectroscopy method at frequency interval from 25Hz up to 1MHz and for cooling from 23{\deg}C to -70{\deg}C. The phase transition near -40{\deg}C was observed. It is supposed that liquid crystal state exists at higher temperatures of point phase transition. For lower temperatures there were two phases, with one of them being ferroelectric.