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Electrocatalytic synthesis of ammonia by surface proton hopping.

ABSTRACT: Highly efficient ammonia synthesis at a low temperature is desirable for future energy and material sources. We accomplished efficient electrocatalytic low-temperature ammonia synthesis with the highest yield ever reported. The maximum ammonia synthesis rate was 30?099 ?mol g_cat^-1 h^-1 over a 9.9 wt% Cs/5.0 wt% Ru/SrZrO₃ catalyst, which is a very high rate. Proton hopping on the surface of the heterogeneous catalyst played an important role in the reaction, revealed by in situ IR measurements. Hopping protons activate N₂ even at low temperatures, and they moderate the harsh reaction condition requirements. Application of an electric field to the catalyst resulted in a drastic decrease in the apparent activation energy from 121 kJ mol^-1 to 37 kJ mol^-1. N₂ dissociative adsorption is markedly promoted by the application of the electric field, as evidenced by DFT calculations. The process described herein opens the door for small-scale, on-demand ammonia synthesis.

SUBMITTER: Manabe R

PROVIDER: S-EPMC5609515 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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Electrocatalytic synthesis of ammonia by surface proton hopping.

Manabe R R Nakatsubo H H Gondo A A Murakami K K Ogo S S Tsuneki H H Ikeda M M Ishikawa A A Nakai H H Sekine Y Y

Chemical science 20170605 8

Highly efficient ammonia synthesis at a low temperature is desirable for future energy and material sources. We accomplished efficient electrocatalytic low-temperature ammonia synthesis with the highest yield ever reported. The maximum ammonia synthesis rate was 30 099 μmol gcat-1 h-1 over a 9.9 wt% Cs/5.0 wt% Ru/SrZrO3 catalyst, which is a very high rate. Proton hopping on the surface of the heterogeneous catalyst played an important role in the react ...[more]

PMID: 28970922

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