Low temperature synthesis of potassium doped barium lead perovskites KxBa1 − xPbO3 − y from hydroxide melts

Perovskite type barium oxoplumbates can be grown at low temperatures via chemical synthesis from alkali hydroxide melts. Strongly oxidizing conditions and low K/Ba ratio lead to the formation of the ternary phase BaPbO3 whereas less oxidizing conditions and high KBa ratio favour the formation of the quaternary solid solution KxBa1−xPbO3−y with tetragonal symmetry. Mixed valence Pbll/PblV quaternary phases can similarly be prepared by anodic deposition from hydroxide melts in closed systems; partial substitution by rare earth ions is possible. Ternary and quaternary oxoplumbates can be reduced electrochemically in aqueous electrolytes at ambient temperature under formation of lead metal.