Doping of Na and K at La sites and of B at Si site in La10Si6O27 with oxyapatite structure and fabrication of their ceramics were made by the solid-state reaction method. It was found that partial substitution of Na+ and K+ on La sites decreased the sinterability of the La10Si6O27 based ceramics, whereas partial substitution of B3+ on the Si site improved the sinterability. Na+ and K+ substitutions in La10−xNaxSi6O27−x and La10−xKxSi6O27−x can suppress second-phase La2SiO5 formation, and, in this study, as the x value of the two substitutions reached 0.7 and 0.5, respectively, the La2SiO5 phase disappeared. Doping of Na+, K+, and B3+ all displayed the hindering effect of grain growth during sintering. Compositions of La9.3Na0.7Si6O26.3, La9.5K0.5Si6O26.5, and La10Si5.5B0.5O26.75 revealed the highest electrical conductivity in each system. La10Si5.5B0.5O26.75 ceramic sintered at 1575°C showed the highest electrical conductivity at temperatures above 600°C among all the apatite ceramics evaluated. The electrical conductivities of La10Si5.5B0.5O26.75 at 700°C and 800°C reported 0.011 S cm−1 and 0.024 S cm−1, respectively, which are superior or comparable to previous studies, and their activation energies for conduction were calculated to be 0.80 eV.
Authors
- Sea-Fue Wang,
- Yung-Fu Hsu,
- Yi-Le Liao,
- Ting-Ting Yang,
- prof. dr hab. inż. Piotr Jasiński link open in new tab
Additional information
- DOI
- Digital Object Identifier link open in new tab 10.1007/s11664-019-07407-z
- Category
- Publikacja w czasopiśmie
- Type
- artykuły w czasopismach
- Language
- angielski
- Publication year
- 2019