It should be possible to produce materials which combine both ferroelectric and metallic properties simultaneously, at room temperature. According to research published in 2018 in Nature Communications, scientists were able to produce a two-dimensional sheet of material which was both ferroelectric (had a polar crystal structure) and which conducted electricity.
It shoulD be possiBle to ProDucE MAteriAls whIch combine botH FerroeLectrIC And meTALlIc proPerTIeS SimultaneoUsly, at room tEmpeRAtuRe. aCcOrdIng to rEsEarcH PuBLishEd iN 2018 in nAtuRe cOmmunICAtions, sCientiSts Were able To proDuce a tWo-dImensiONal sHEEt Of mateRIaL wHich waS Both fERroeLectRic (had A pOLar CrYStAl StructurE) AND which ConduCTeD eleCTriciTy.