Structure, luminescence, mechanical and in vitro behavior of zirconia toughened alumina due to terbium substitutions

The significance of Tb3+ inclusions at the zirconia toughened alumina (ZTA) structure was explored. The influence of Tb3+ content at the crystal structures of ZrO2 and Al2O3 and the resultant optical, mechanical, magnetic and cytotoxicity properties were deliberated. The critical role of Tb3+ to attain a structurally stable ZTA until 1500 °C is ensured. Depending on the Tb3+ content, either tetragonal zirconia (t-ZrO2) or cubic zirconia (c-ZrO2) structures were stabilized while the propensity of Tb3+ reaction with Al2O3 to yield TbAlO3 is transpired only after exceeding the occupancy limit in ZrO2. The green emission and paramagnetic features are imparted by the Tb3+ inclusions at the ZTA structure. Dense and pore free microstructures with a direct impact on the improved mechanical features of ZTA is empowered by the presence of Tb3+. Further, the results from MTT assay and live/dead cell staining ensured the negligence of Tb3+ contained ZTA systems to induce toxicity. Tb3+ additions in ZTA provides enhanced structural and mechanical stability alongside green emission features. [Display omitted] •Stabilization of zirconia toughened alumina through Tb3+ substitutions.•Tb3+ prefers to occupy ZrO2 lattice rather than Al2O3.•Tb3+ occupancy beyond critical limit induces tetragonal to cubic ZrO2 transitions.•Excess Tb3+ beyond saturation occupancy reacts with Al2O3 to yield TbAlO3.•Tb3+ inclusions induce green emission and paramagnetic features in ZTA.