Sintering and microstuctural characterization of W6+, Nb5+ and Ti4+ iron-substituted BiFeO3

The sintering behaviour and the microstructural evolution of W6+, Nb5+ and Ti4+ iron-substituted BiFeO3 ceramics have been analyzed. The obtained results show that W6+ and Nb5+ ions interact with the secondary phases usually present in these materials, thus altering the solid state formation of the BiFeO3 phase. In contrast, Ti4+ ions incorporate into the perovskite structure, leading to an exceptionally low proportion of secondary phases. In addition to this, BiFe0.95Ti0.05O3 materials present a dense microstructure with submicronic and nanostructured grains, clearly smaller than those in the undoped materials.

► Undoped and doped BiFeO3 ceramics are prepared by a solid-state synthesis route. ► Addition of W6+ and Nb5+ leads to the formation of high amount of secondary phases. ► Ti4+ ions enter the perovskite structure and stabilize the BiFeO3 phase. ► Ti-doped materials show extraordinary low proportion of secondary phases. ► BiFe0.95Ti0.05O3 materials show a dense microstructure with nanostructured grains.