Simultaneous accommodation of Dy 3+ at the lattice site of β‐ Ca 3 (PO 4 ) 2 and t ‐ZrO 2 mixtures: Structural stability, mechanical, optical, and magnetic features

• Published in: Journal of the American Ceramic Society 2020-06, Vol.103 (6), p.3528-3540
• Main Authors: Nandha Kumar, Ponnusamy, Subramanian, Shangavi, Vijayalakshmi, Uthirapathy, Kannan, Sanjeevi
• Format: Article
• Language: English
• ISSN: 0002-7820; 1551-2916
• DOI: 10.1111/jace.17056

Structurally stable β‐ Ca 3 (PO 4 ) 2 / t ‐ZrO 2 composite mixtures with the aid of Dy 3+ stabilizer were accomplished at 1500°C. The precursors comprising Ca 2+ , P 5+ , Zr 4+ , and Dy 3+ have been varied to obtain five different combinations. The results revealed the fact that complete phase transformation of calcium‐deficient apatite to β‐ Ca 3 (PO 4 ) 2 occurred only at 1300°C, whereas the evidence of t ‐ZrO 2 crystallization is obvious at 900°C. The dual occupancy of Dy 3+ at β‐ Ca 3 (PO 4 ) 2 and t ‐ZrO 2 structures was evident; however, Dy 3+ initially prefers to occupy β‐ Ca 3 (PO 4 ) 2 lattice until its saturation limit and thereafter accommodates at the lattice site of ZrO 2 . The typical absorption and emission behavior of Dy 3+ were noticed in all the systems and, moreover, the surrounding symmetry of Dy 3+ domains has been determined from the luminescence study. All the systems ensured paramagnetic response that is generally contributed by the presence of Dy 3+ . A gradual increment in the phase content of t ‐ZrO 2 in the composite mixtures ensured a significant improvement in the hardness and Young's modulus of the investigated compositions.