Reaction Analysis of Electrochemical Synthesis of Ammonia with Proton Conducting BaCe_(0.9)Y_(0.1)O_3 Solid Electrolyte

摘要

Electrochemical synthesis of ammonia was performed using a mixed protonic and electronic conducting cathode, Ru-doped BaCe_(0.9)Y_(0.1)O_3 (BCYR), with proton conducting solid electrolyte at 500°C. BCYR with 0-20% of Ru-doping were synthesized and characterized using XRD, XPS and TEM. TEM images and XPS measurement showed the formation of Ru nanoparticles on the BCYR surface after a heat treatment in reducing atmosphere. Electrochemical synthesis of ammonia was performed with BCYR|BaCe_(0.9)Y_(0.1)O_3(BCY)|Pt and Ni-BCYR|BCY|Pt cells. Ni-BCYR cathode showed higher ammonia formation rate in comparison with that using BCYR cathode or Ru-based cathode reported previously. The result suggests that the mixed protonic and electronic conduction of the cathode may contribute to increase of active Ru nanoparticles for the electrochemical ammonia synthesis. On the other hand, the Faraday efficiency of ammonia formation for the BCYR cathode was higher than that for the Ni-BCYR cathode. For further efficient ammonia synthesis, preventing hydrogen production and improving protonic and electronic transport properties in the cathode are important.