Electrochemical synthesis of ammonia from N2 and H2O based on (Li, Na, K) 2CO3–Ce0. 8Gd0. 18Ca0. 02O2− δ composite electrolyte and CoFe2O4 cathode

Electrochemical synthesis of ammonia from water vapour and nitrogen was investigated
using an electrolytic cell based on CoFe2O4eCe0.8Gd0.18Ca0.02O2d (CFO-CGDC), CGDCternary
carbonate composite and Sm0.5Sr0.5CoO3deCe0.8Gd0.18Ca0.02O2d (SSCo-CGDC) as
cathode, electrolyte and anode respectively. CoFe2O4, CGDC and SCCo were prepared via a
combined EDTA-citrate complexing solegel and characterised by X-ray diffraction (XRD).
The AC ionic conductivities of the CGDC-carbonate composite were investigated under
three different atmospheres (air, dry O2 and wet 5% H2eAr). A tri-layer electrolytic cell was
fabricated by a cost-effective one-step dry-pressing and co-firing process. Ammonia was
successfully synthesised from water vapour and nitrogen under atmospheric pressure and
the maximum rate of ammonia production was found to be 6.5 1011 mol s1 cm2 at
400 C and 1.6 V which is two orders of magnitude higher than that of previous report when
ammonia was synthesised from N2 and H2O at 650 C.
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