Structural and conductivity properties of K doped Ba4Ca2Nb2O11 (BCN) complex perovskite for energy applications

Developing new proton and oxide ion conducting material with better stability is of great importance for the performance enhancement of devices for energy related applications. In this work Ba1-xKx(-Ca0.5Nb0.5)O2.75-delta (x = 0, 0.25, 0.50, 0.75 and 1) complex perovskites were synthesised through solid state reaction route. The XRD patterns of calcined samples showed the formation of single phase double perovskite structure having favourable crystal lattice for oxygen vacancies for achieving enhanced proton and oxide ion conductivity. The investigated K doped BCN perovskite with 25% dopant concentration exhibited both higher total conductivity and stability when compared to the undoped BCN perovskite. This enhancement in total conductivity is suggested to be due to increase in number of oxygen vacancies on doping. These results are encouraging considering the stability and higher oxide ion conductivity. (C) 2016 Elsevier B.V. All rights reserved.