The search for a light, high-capacity hydrogen store continues. Ammonia borane (AB) is a complex hydride with excellent hydrogen capacity, of which half desorbs at moderate temperatures (100-170 C). We can nanostructure this material by encapsulation in an H-permeable polymer sheath using the electrospinning process to produce co-axial AB nanofibres. This should improve the desorption kinetics, reduce the H diffusion distance and move the desorption temperature closer to ambient conditions, retaining the nanostructure while suppressing harmful byproduct emission. We propose to explore the differences in H2 evolution between bulk AB and the nanofibres using QENS on IRIS, in situ diffraction, isochoric desorption and mass spectrometry to explore the AB melting and diffusion using 11B-enriched AB. For this we will study sheath polymers, two AB co-axial fibres and bulk AB from 270 to 600 K