A5012585238- Ammonia Synthesis and Nitrogen Reduction
- Hydrogen Storage and Materials
- Nanomaterials for catalytic reactions
- Catalytic Processes in Materials Science
- Advanced Photocatalysis Techniques
- Caching and Content Delivery
- Chemical Synthesis and Characterization
- Molten salt chemistry and electrochemical processes
University of Oxford
2018-2023
Science Oxford
2018
Ammonia is regarded as an energy vector for hydrogen storage, transport and utilization, which links to usage of renewable energies. However, efficient catalysts ammonia decomposition their underlying mechanism yet remain obscure. Here we report that atomically-dispersed Ru atoms on MgO support its polar (111) facets {denoted MgO(111)} show the highest rate decomposition, far are aware, than all reported in literature due strong metal-support interaction surface coupling reaction. We have...
Direct electrochemical synthesis of ammonia is proposed as a means reducing the carbon footprint fertiliser industry, well providing new opportunities for carbon-free liquid energy storage. We review current status research into materials and evaluate reported rates efficiencies in terms recent US Department Energy targets. Surprisingly, development electrocatalysts has only recently received much attention, despite number promising rates, target values remain distant. A theoretical studies...
Abstract There is an exciting possibility to decentralize ammonia synthesis for fertilizer production or energy storage without carbon emission from H 2 obtained renewables at small units operated lower pressure. However, no suitable catalyst has yet been developed. Ru catalysts are known be promoted by heavier alkali dopants. Instead of using heavy metals, Li herein shown give the highest rate through surface polarisation despite its poorest electron donating ability. This exceptional...
Barium zirconate perovskites have been systematically investigated as protonic supports for ruthenium nanoparticles in the Haber–Bosch ammonia synthesis reaction. A series of based on barium were synthesized, which B-site ABO3 perovskite was doped with different aliovalent acceptor cations and varying ratios, resulting proton conductivities trapping behaviors. Crucially, we provide direct evidence importance a hydrogen-migration mechanism over these proton-conducting materials from studies...
Abstract Molten LiCl and related eutectic electrolytes are known to permit direct electrochemical reduction of N 2 3− with high efficiency. It had been proposed that this could be coupled H oxidation in an electrolytic cell produce NH 3 at ambient pressure. Here, proposal is tested a LiCl–KCl–Li found not the case, as previous assumption grossly over‐simplified. We find Li added molten electrolyte promotes spontaneous simultaneous chemical disproportionation (H state 0) into − −1) + form 2−...
Fixation of nitrogen to ammonia (N 2 (g) + 3H ⇌ 2NH 3 ) is firmly established as one the most important chemical processes for humanity. Global production in 2016 reached 144 million tons, with 88% being used fertiliser production. 1 Ammonia currently produced through Haber process, requiring temperatures 300-500 o C and pressures 150-200 bar. This associated high CO emissions, made worse by fact that hydrogen process comes from steam reformation methane. A suggestion decarbonise uses...
Ammonia is one of the most significant chemical products on planet due to its central role in agriculture, as well use a wide variety processes. More recently it has also attracted interest carbon-free energy vector, with an density similar that methanol and immediate compatibility existing storage distribution infrastructure. Current ammonia production relies natural gas for both hydrogen required by high temperature, pressure Haber-Bosch reaction. This technology consumes over 1% all...
Ammonia is one of the most important base chemicals in world being a quintessential ingredient fertilizers. It produced on mega ton per year scale by Haber-Bosch process from hydrogen and nitrogen at temperatures around 400-500°C pressures up to 200 atmospheres contributing approximately 2% global CO 2 emissions. 1 A promising alternative for small applications electrochemical ammonia production utilizing molten salts as electrolytes. Such systems work ambient pressure, moderate temperature...