Abstract
Advanced catalysts for ammonia (NH3) decomposition reaction hold great promise in the area of renewable energy. In this work, highly dispersed molybdenum nitride (MoN/Mo2N) nanocrystals anchored on in-situ assembled two-dimensional (2D) mesoporous silica/reduced graphene oxide (rGO) hybrid nanosheets (MoN/SBA-15/rGO and Mo2N/SBA-15/rGO) were designed and synthesized as active and stable catalysts for COx-free H2 generation via NH3 decomposition. Benefiting from well-defined molybdenum nitride nanocrystals and moderate MoN band strength, the nanohybrids exhibited superior catalytic property, especially Mo2N/SBA-15/rGO with the highest NH3 decomposition rate of 30.58 mmol g−1cat min−1 among any Mo-based catalysts reported to date. Density functional theory (DFT) calculations revealed that the superior catalytic activity for Mo2N compared to MoN stemmed from a large reduction of kinetic energy barriers of dehydrogenation and nitrogen desorption. Moreover, the introduction of rGO can effectively weaken the associative desorption of adsorbed N atoms and thus improve NH3 decomposition activity. This study highlights the importance of designing spatially confined metal nitrides for enhancing energy catalysis.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have