A‐site acceptor‐doping strategy to enhance oxygen transport in sodium–bismuth–titanate perovskite

Sodium–bismuth–titanate (NBT) has recently been shown to contain high levels of oxide ion conductivity. Here we report the effect A-site monovalent ions, M+ = K+ and Li+, on electrical conductivity NBT. The partial replacement Bi3+ with ions improved ionic by over one order magnitude without an apparent change conduction mechanism, which is attributed increase in oxygen vacancy concentration based acceptor-doping approach. 18O tracer-diffusion coefficient (D*) determined isotope exchange depth profile method combination secondary mass spectrometry confirmed that are main charge carriers system. Among these acceptor-doped samples, 4% Li doping provides highest total conductivity, leading a further discussion strategies for NBT-based materials enhance behavior, discussed. Comparisons other oxide-ion conductors oxygen-vacancy diffusivity limit model perovskite lattice suggested doped might already have achieved optimization