Improved ionic conductivity in NdGdZr2O7: Influence of Sc3+ substitution

Highly dense Sc3+ doped pyrochlores, NdGdZr2−xScxO7−δ (0.0 ≤ x ≤ 0.15), have been prepared by gel combustion method followed by sintering at high temperature. Additional oxygen vacancy could be induced by doping of Sc3+ at the site of Zr4+ in the titled composition. Structural studies indicate the presence of disorder in Sc doped samples. The decrease in lattice parameter upon Sc3+ doping at Zr4+ site attributes to oxygen vacancy. The oxygen vacancy helped to achieve the high density. Increased number of mobile species and additional oxygen vacancy in the Sc doped samples make them excellent ionic conductor.