Yang T.,University of Science and Technology Beijing |
Zhao H.,University of Science and Technology Beijing |
Zhao H.,Beijing Key Laboratory of New Energy Materials Science and Technology |
Han J.,University of Science and Technology Beijing |
And 4 more authors.
Journal of the European Ceramic Society | Year: 2014
Lanthanum silicate apatite (LSA, La9.33+xSi6O26+1.5x, x=0-0.67) has been widely investigated as a promising electrolyte material for intermediate temperature solid oxide fuel cell (SOFC). In this work, a facile and low-cost co-precipitation method is used to synthesize LSA precursor powders. The well dispersed nanopowders (ca. 70nm) with pure hexagonal LSA phase are obtained by calcining the precursor at 900°C. Impurity of La2SiO5, caused by the different precipitation productivities of La(NO3)3 and TEOS, can be eliminated through lowering the La/Si ratio in the starting mixtures. The dispersant (PEG200) plays a crucial role in co-precipitation processes, which can effectively mitigate the agglomeration and therefore significantly improve the sinterability of the nanoparticles. Dense LSA ceramic with relative density of 98% is obtained after sintering at 1550°C, which exhibits a conductivity of 0.13mScm-1 at 500°C. © 2013 Elsevier Ltd.