Designing an Iron-Based Bis(pyridyl)borate Complex Catalyst for Ammonia-Borane Dehydrogenation Using Density Functional Theory

Although Ammonia-borane (AB) has considerably high hydrogen content, it faces significant challenges as an on-board hydrogen storageHydrogen storage material due to its sluggish dehydrogenation kinetics. It is essential to find an efficient and cost-effective catalytic system for AB dehydrogenationAmmonia Borane Dehydrogenation catalyst. Herein, we design an iron-based catalyst, Fe-Bis(pyridyl)borate complex (Fe-CAT_Ph–OH) which is a cost-effective counterpart of a promising but expensive Ru-Bis(pyridyl)borate complex (CAT). This new Fe-system has three aceto-iso-nitrile ligands instead of acetonitrile ligands with a Ph–OH group substituted at its µ–O–B position. Also, the proton at the µ–OH group has been replaced by a –CH₃ group to avoid its derivatization. The free-energy energetic span for AB dehydrogenationAmmonia Borane Dehydrogenation by Fe-CAT_Ph–OH 32.13 kcal/mol suggests that this catalyst is likely to operate effectively at around 90°C. This work demonstrates a protocol to tune the existing catalyst without significantly affecting their functionality under experimental conditions.