Thermal conductivity of ammonia borane complex and its composites with aluminum powder

Abstract

The thermal conductivity of ammonia borane (AB) complex, in the temperature range of 300–420 K, was measured experimentally using ASTM method E 1225. At 300 K, the thermal conductivity of pure AB was found to be approximately 15 W/m-K. A composite pellet prepared by mixing 10 wt% aluminum powder with AB had a thermal conductivity that was a factor of 4 higher than that of pure AB complex. The extent of the pyrolytic weight loss for AB/Al composite and pure AB complex was 25.4% and 33.9%, respectively—indicating comparatively lower levels of volatile species evolved as impurities (e.g. monomeric aminoborane, borazine, diborane, etc.) in the product hydrogen.