Accelerated Thermal Decomposition of Ammonia Borane by Carbon Dioxide

This talk presents the enhanced dehydrogenation of ammonia borane (AB) at 85 ^oC under CO2, an abundant and naturally occurring material. The presence of CO₂ significantly accelerates the thermal decomposition and it kinetics becomes faster as the CO₂ pressure increases from 1.70 to 3.67 bar. Around 4 bar of CO₂, 1.33 equivalents of hydrogen is released from AB in 1 hour. The accelerated AB thermolysis is attributed to CO₂ reacting with AB, or intermediates like diammoniate of diborane (DADB), or primary thermolysis products including linear dimers of aminoborane (LDAB), which accelerates AB thermolysis, and this reaction has been confirmed by ATR-FTIR, Raman, and ¹¹B and ¹³C solid sate MAS-NMR measurements. The results open up a potential avenue to convert CO₂ to other useful chemicals under very mild conditions.