Enhancing the thermal dehydrogenation properties of ammonia borane (AB) by using monodisperse MnO2 hollow spheres (MHS)

In this paper, we report on a hydrogen storage material: MnO2 hollow spheres and ammonia borane (MHS/AB) composite, which is fabricated by a simple liquid mixing method. The BET, SEM and TEM results show that AB is well loaded in the MnO2 hollow spheres. The thermal dehydrogenation processes are investigated by thermogravimetry (TG), Differential scanning calorimetry (DSC), temperature programmed desorption/mass spectrometer (TPD/MS) measurements. The results show that the MHS/AB composites exhibit enhanced thermal dehydrogenation properties with lower dehydrogenation temperature (101 °C) compared to pure AB (117 °C). The kinetic analysis revealed that the apparent activation energies (Ea) of the dehydrogenation showed remarkable reduction for the MHS/AB composite (68.5 kJ/mol), as compared to the pristine AB (207.7 kJ/mol). Furthermore, the unwanted volatile byproducts and volume expansion of AB are suppressed. •Mono-dispersed MnO2 hollow spheres as nanoscaffold materials have been synthesized.•MHS/AB composites have been synthesized by a simple solution process at room temperature.•The dehydrogenation performance of the MHS/AB system was investigated.•3MHS/AB significantly modified dehydrogenation properties of neat AB.