Influence of the rare earth (R) element in Ru-supported RScSi electride-like intermetallic catalysts for ammonia synthesis at low pressure: insight into NH3 formation mechanism

Data set from Influence of the rare earth (R) element in Ru-supported RScSi electride-like intermetallic catalysts for ammonia synthesis at low pressure: insight into NH3 formation mechanism - Publication : Croisé C., Alabd K., Tencé S., Gaudin E., Villesuzanne A., Courtois X., Bion N. and Can F. Influence of the rare earth (R) element in Ru-supported RScSi electride-like intermetallic catalysts for ammonia synthesis at low pressure: insight into NH3 formation mechanism. ChemCatChem 2023 vol.15, n°3, p. e202201172 (12 p.). HAL : https://hal.science/hal-03992609 Dataset production context : This study investigates the influence of the rare-earth (R) element in Ru/RScSi electride-like intermetallic catalysts for ammonia synthesis under mild conditions (300–450 °C; 1–5 bar). All materials present poor specific surface area and the grain size impacts the ammonia yield. The catalytic performances follow the La to Gd lanthanides series (Ru1.7/LaScSi=Ru1.7/CeScSi=Ru1.7/PrScSi>Ru1.7/NdScSi>Ru1.5/SmScSi>Ru1.3/GdScSi) and appear correlated with the formation of the hydride phase. Ru1.7/CeScSi shows remarkable catalytic activity under moderate condition (0.58 mmolNH3/h/g at 300 °C, 1 bar) associated with its reversible hydrogen storage–release properties. It is evidenced that RScSi materials assist the N2 dissociation in agreement with their electride character and that the hydrogen for NH3 formation mainly comes from gaseous hydrogen and not primarily from the hydride phase. It is suggested that NHX formation could be the rate determining step rather than the N2 cleavage over these catalysts. For more information see the article.