Superdielectric Materials Composed of NaCl, H2O and Porous Alumina

Abstract

To test a theory of the recently discovered phenomenon of superdielectric behavior the dielectric constants of several ‘pastes’ composed of porous alumina powders filled to the point of incipient wetness with water containing dissolved sodium chloride, were measured. The dielectric constants of some of the pastes were greater than 1010, higher than that of any material ever reported. These results are consistent with this recently postulated model of superdielectric behavior in porous, non-conductive materials saturated with ion-containing liquids: Upon the application of an electric field ions dissolved in the saturating liquid contained in the pores will travel to the ends of pore filling liquid droplets creating giant dipoles. The fields of these giant dipoles oppose the applied field, reducing the net field created per unit of charge on the capacitor plates, effectively increasing charge/voltage ratio, hence capacitance. Other observations reported herein include; i) the impact of ion concentration on dielectric values, ii) a maximum voltage similar to that associated with the electrical breakdown of water, iii) the loss of capacitance upon drying, and iv) the recovery of capacitance upon the addition of water to a dry super dielectric material. All observations are consistent with the earlier proposed model of the super dielectric phenomenon.