Quantitative Control of Oxygen Non-Stoichiometry and Negative Raman Chemical Shift During Topotactic Phase Transition in a Ca-Doped BiFeO Thin-Film.

Controlling the non-stoichiometry is an effective way to tune physicochemical properties of functional oxides and explore novel physical phenomena in complex oxides. Therefore, quantitative control of oxygen non-stoichiometry in perovskite oxides plays an important role in understanding the mechanism of topotactic phase transition and improving the applicability of electrochemical devices. Here, an electrochemical titration cell is fabricated to control the oxygen non-stoichiometry of a BiCaFeO thin film grown on yttria-stabilized zirconia substrate.