Tailored metal-ceramic nanocomposites prepared by redox cycling of polycrystalline Ni-doped yttria stabilized zirconia

摘要

We demonstrate it possible to tailor unique metal-ceramic nanocomposites through redox cycling of Y2O3-stabilized ZrO2 containing 0.5 molar percent NiO (below the solubility limit). Upon the first reduction, Ni2+ ions precipitate as metallic Ni-0 at pores, grain boundaries, or within the grain interiors with specific size ranges (similar to 5 nm/similar to 30 nm/similar to 200 nm) for each. Upon oxidation, Ni2+ ions form, but their distribution is not the same as the original microstructure. In particular, NiO forms, and subsequent reduction leads to a distribution of metallic Ni different from that in the first reduction. One can ratchet the dissolution/precipitation behavior to form particular nanoscale arrangements. (C) 2015 Elsevier Ltd. All rights reserved.