A method and apparatus for forming variable density ceramic structures, where the method includes: obtaining a ceramic powder having an ultrafine particle size; mixing the ceramic powder into a suspension fluid thus forming a ceramic suspension; providing a mold configured to retain the ceramic suspension; providing a plurality of electrodes about the mold; applying an alternating voltage to the electrodes thus forming alternating electric currents through the suspension thus causing accumulation of ceramic particles on at least one of the electrodes; reducing the temperature of the suspension thus inducing the formation of ice crystals therein necessary for ice-templating; freeze drying the frozen suspension into a porous state; and sintering the ceramic particles into a solid architecture retaining a common final structure with the ceramic particles in the porous state.