b'Investigation of molecularEngineering the interfacial electrolyte structuring is integral to and interfacial processesdrive ambient nitrogen reduction to ammonia in ionic liquids.of the electrocatalyticA mmonia is a highly desired hydrogen storage and energy carrier medium. As a sustainable alternative to the industrial Haber-Bosch process, conversion of nitrogenprogress in ambient nitrogen reduction reaction to ammonia has been to ammonia undermainly constrained by the slow pace of designing efficient electrocatalyst systems. In screening for potential catalyst systems, major efforts have been devoted to surface ambient conditions usingand electrolyte development, often based on bulk reactivity analyses. Unraveling the rare earth element andkey interfacial factors dictating the conversion efficiency would offer a more coherent strategy to accelerate the development of robust catalytic platforms for ambient room temperature ionicnitrogen reduction reaction. liquid-based system Our approach was to focus on the molecular structure at the electrode-solution interface and to link experimental observation with electrocatalytic performance. Paramount was the demonstration that our developed interface sensitive approaches based on novel surface modification with robust and continuous layers of boron-doped diamond and gold were key to both detect nitrogen reduction reaction and to isolate the molecular composition directly adsorbed on the electrocatalyst from PROJECT NUMBER:that in the sub-surface regime. Our results indicate that nitrogen reduction in ionic 22A1059-040FP liquid media, in contrast to aqueous systems, is sluggish at best in the absence of a suitable proton donor. Whereas direct spectroscopic evidence of nitrogen TOTAL APPROVED AMOUNT: reduction reaction products can be obtained in high pH aqueous electrolytes using a$700,000 over 2 years moderately active electrocatalyst, no such evidence was forthcoming in neat and wet PRINCIPAL INVESTIGATOR:ionic liquid media. We attributed this to an inaccessible proton source at the interface Abderrahman Atifi that suppresses the nitrogen reduction reaction efficiency in ionic liquid media. Our studies indicate that this is highly correlated to the potential-induced formation of a CO-INVESTIGATORS: patchy condensed phase of ionic liquid ions strongly adsorbed to the metal surface. Dong Ding, INL The dynamics of this phase formation are complex, but we conclude that the process Meng Li, INL is highly irreversible. Our results suggest that engineering such interfacial structuring Robert Fox, INL is a critical component that must be pursued if better nitrogen reduction reaction Ian Burgess, University of Saskatchewancatalytic efficiency is to be realized. Capitalizing on our findings, initial design experiments targeting a homogenized and less dense and hydrophobic ionic liquid interface seem to support our perspectives on the critical role of proton accessibility at the interface to form ammonia. Therefore, we stress that the innermost layer of the electrolyte system is integral to the reaction efficiency and thus it is the interfacial electrolyte organization and not the bulk system that must be properly engineered. The collaboration with the University of Saskatchewan helped establish a unique in situ surface sensitive spectroscopic capability at INL.128'