title: Kinetics of Ice Nucleation Confined in Nanoporous Alumina.
abstract: The nucleation mechanism of water (heterogeneous/homogeneous) can be regulated by confinement within nanoporous alumina. The kinetics of ice nucleation is studied in confinement by employing dielectric permittivity as a probe. Both heterogeneous and homogeneous nucleation, obtained at low and high undercooling, respectively, are stochastic in nature. The temperature interval of metastability extends over ∼4 and 0.4 °C for heterogeneous and homogeneous nucleation, respectively. Nucleation within a pore is spread to all pores in the template. We have examined a possible coupling of all pores through a heat wave and a sound wave, with the latter being a more realistic scenario. In addition, dielectric spectroscopy indicates that prior to crystallization undercooled water molecules relax with an activation energy of ∼50 kJ/mol, and this process acts as precursor to ice nucleation.
authors.affiliation: Max Planck Institute for Polymer Research , 55128 Mainz, Germany.
authors.forename: Yasuhito
authors.initials: Y
authors.lastname: Suzuki
authors.affiliation: Institut für Chemie neuer Materialien, Universität Osnabrück , D-49069 Osnabrück, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Steinhart
authors.affiliation: Max Planck Institute for Polymer Research , 55128 Mainz, Germany.
authors.forename: Hans-Jürgen
authors.initials: HJ
authors.lastname: Butt
authors.affiliation: Department of Physics, University of Ioannina , 45110 Ioannina, Greece.
authors.forename: George
authors.initials: G
authors.lastname: Floudas