Assemblies of energetic 3,3′-diamino-4,4′-azofurazan on single-walled carbon nanotubes

► We investigated the properties of the DAAzF assembled inside or outside three CNTs. ► The assembling process of DAAzF outside CNTs favors in energy. ► DAAzF can spontaneously assemble inside CNTs of larger diameter. ► The nature of DAAzF was not modified by the assembling outside the CNTs. ► The DAAzF assembled inside the CNT of small diameter showed very different properties.