301. Structural and Electrochemical Properties of Lanthanum Silicate Apatites La10Si6−x−0.2AlxZn0.2O27−δ for Solid Oxide Fuel Cells (SOFCs)
- Author
-
Saeed Nekoonam, Hidayatul Qayyimah Hj Hairul Absah, Jun-Young Park, Sumon Reza, Abul Kalam Azad, Alibek Issakhov, Mahendra Rao Somalu, and Shammya Afroze
- Subjects
Materials science ,Dopant ,Article Subject ,Scanning electron microscope ,020209 energy ,General Chemical Engineering ,Oxide ,Analytical chemistry ,chemistry.chemical_element ,02 engineering and technology ,021001 nanoscience & nanotechnology ,Dielectric spectroscopy ,Crystallinity ,chemistry.chemical_compound ,Chemical engineering ,chemistry ,Impurity ,0202 electrical engineering, electronic engineering, information engineering ,Lanthanum ,Solid oxide fuel cell ,TP155-156 ,0210 nano-technology - Abstract
An excellent oxide ion conductivity with high oxygen transportation of lanthanum silicate apatite at the solid oxide fuel cell (SOFC) can be achieved through the solid-state reaction method. The doped La10Si6−x−0.2AlxZn0.2O27−δ (x = 0.2 and 0.4) materials sintered at 1600°C accomplished crystallinity and crystal structure of apatite-type. The structural and electrochemical characterizations of La10Si6−x−0.2AlxZn0.2O27−δ (x = 0.2 and 0.4) were executed using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and electrochemical impedance spectroscopy (EIS) measurements. The total oxide ion conductivities of La10Si6−x−0.2AlxZn0.2O27−δ (x = 0.2 and 0.4) were measured from low to intermediate operating temperature range (450 to 800°C) using electrochemical impedance spectroscopy. Room temperature XRD patterns of La10Si6−x−0.2AlxZn0.2O27−δ (x = 0.2 and 0.4) exhibited La10Si6O27 apatite phase with space group P63/m as the main phase with the minor appearance of La2SiO5 as an impurity phase. The highest total oxide ion conductivity of 3.24 × 10−3 Scm−1 and corresponding activation energy of 0.30 eV at 800°C were obtained for La10Si5.6Al0.2Zn0.2O26.7 which contains a low concentration of Al3+ dopant.
- Published
- 2021
- Full Text
- View/download PDF