Ammonia for hydrogen storage: challenges and opportunities

TitleAmmonia for hydrogen storage: challenges and opportunities
Publication TypeJournal Article
Year of Publication2008
AuthorsKlerke A, Christensen CH, Norskov JK, Vegge T
JournalJournal of Materials Chemistry
Date PublishedMay 28
ISBN Number0959-9428
Accession Number
Keywordscox-free hydrogen, decomposition, economy, fuel-cell applications, h-2 desorption, kinetics, libh4, mg(nh3)(6)cl-2, miniaturized production, performance

The possibility of using ammonia as a hydrogen carrier is discussed. Compared to other hydrogen storage materials, ammonia has the advantages of a high hydrogen density, a well-developed technology for synthesis and distribution, and easy catalytic decomposition. Compared to hydrocarbons and alcohols, it has the advantage that there is no CO2 emission at the end user. The drawbacks are mainly the toxicity of liquid ammonia and the problems related to trace amounts of ammonia in the hydrogen after decomposition. Storage of ammonia in metal ammine salts is discussed, and it is shown that this maintains the high volumetric hydrogen density while alleviating the problems of handling the ammonia. Some of the remaining challenges for research in ammonia as a hydrogen carrier are outlined.