Synthesis of BaBiO₃ and Ba_1-xK_xBiO₃ films via an electrodeposition process

Films of BaBiO₃ and Ba_1-xK_xBiO₃ were prepared via an electrodeposition process. The process consists of a codeposition of the metals of the phases from a single electrolyte at -3.5 V (vs. Ag/AgCl) followed by oxidation at 700°C in air. The desired metal stoichiometries were obtained by regulating the electrolyte bath composition. X-ray diffraction data showed that the films of the different preparations consisted of a single phase after oxidation. Strong dependence of the morphology of the films on the composition of the oxide was observed. Superconducting transitions at ∼ 35 K were obtained in the Ba_0.8(1)K_0.2(1)BiO₃ phase. This seems to be the first occasion in what these materials have been obtained as a film by this method.