Thermal Decomposition and Spectroscopic Studies of Preheated Ammonia Borane

• DOI: 10.1021/jp105014t
• Publication Date: 2010-10-26T17:09:27Z
• Authors: Junshe Zhang; Yu Zhao; Daniel L. Akins; Jae W. Lee
• Keywords: Ammonia Borane; Diborane

This paper presents enhanced dehydrogenation of solid ammonia borane (AB, NH3BH3) at 85 °C after it was preheated 80 for 2−4 h. Thermal treatments and subsequent hydrogen release experiments were carried out in a Hastelloy cell mounted on high-pressure differential scanning calorimeter. With increased preheating durations, not only does the induction period shorten but also becomes fast. It is deduced that diammoniate diborane (DADB, [(NH3)2BH2]+[BH4]−), oligomers or polymers, AB form solution, shifting melting temperature to low value. Hydrogen evolution, as result initial stage oligomerization, observed maintaining pristine 20 min. FTIR-ATR spectra thermally treated indicated linear dimers aminoborane (LDAB, NH3BH2NH2BH3) are detected periods shorter than 3 h, whereas other polymers longer thermal treatment °C.