NJC
Paper
the compensating effects of the slowly declining oxide ion References
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According to the above discussion, the reduction mechanism
of the ZrSiO4–SiO2 cathode by the electrochemical deoxidation
process is schematically proposed in Fig. 9. Firstly, by the reaction
of CaO with ZrSiO4 or SiO2, the calcium silicates (CaSiO3, Ca2SiO4)
and CSZ (CaxZr1ÀxO2Àx) intermediate phases were formed in
the cathode and located at the same place. Secondly, the
calcium silicates (CaSiO3, Ca2SiO4) and CSZ (CaxZr1ÀxO2Àx
)
were simultaneously reduced into Si and Zr respectively, which
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Acknowledgements
The authors acknowledge the financial support of the National 25 C. Schwandt and D. J. Fray, Z. Naturforsch., A: Phys. Sci.,
Natural Science Foundation of China (Grant No. 51174055). 2007, 62, 655–670.
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