Dispersed surface Ru ensembles on MgO(111) for catalytic ammonia decomposition.

Ammonia is regarded as an energy vector for hydrogen storage, transport and utilization, which links to usage of renewable energies. However, efficient catalysts for ammonia decomposition and their underlying mechanism yet remain obscure. Here we report that atomically-dispersed Ru atoms on MgO support on its polar (111) facets {denoted as MgO(111)} show the highest rate of ammonia decomposition, as far as we are aware, than all catalysts reported in literature due to the strong metal-support interaction and efficient surface coupling reaction.

Efficient Non-dissociative Activation of Dinitrogen to Ammonia over Lithium-Promoted Ruthenium Nanoparticles at Low Pressure.

There is an exciting possibility to decentralize ammonia synthesis for fertilizer production or energy storage without carbon emission from H obtained from renewables at small units operated at lower pressure. However, no suitable catalyst has yet been developed. Ru catalysts are known to be promoted by heavier alkali dopants.

The Feasibility of Electrochemical Ammonia Synthesis in Molten LiCl-KCl Eutectics.

Molten LiCl and related eutectic electrolytes are known to permit direct electrochemical reduction of N to N with high efficiency. It had been proposed that this could be coupled with H oxidation in an electrolytic cell to produce NH at ambient pressure. Here, this proposal is tested in a LiCl-KCl-Li N cell and is found not to be the case, as the previous assumption of the direct electrochemical oxidation of N to NH is grossly over-simplified.

Materials for electrochemical ammonia synthesis.

Direct electrochemical synthesis of ammonia is proposed as a means of reducing the carbon footprint of the fertiliser industry, as well as providing new opportunities for carbon-free liquid energy storage. We review the current status of research into materials for electrochemical ammonia synthesis and evaluate the reported rates and efficiencies in terms of recent US Department of Energy targets. Surprisingly, development of electrocatalysts has only recently received much attention, and despite a number of promising rates, the target values remain distant.