Abstract
Cu induced catalytic growth of complex nanotubes has been demonstrated for the first time. With constituent unit of dihexadecylamine μ-sulfato zinc(II) complex, multi-hydrophobic interactions direct the self-assembly behavior and lead to the nanotube aggregates. Length-tunability has also been achieved simply by varying the precursor concentration. Intense light scattering resonance from nanotubes shows size-dependent optical properties. Due to highly-ordered packing inside our nanotubes, the enhanced structural stability promises possible device applications. Extraordinarily high thermal-resistance property of self-assembled supramolecular nanotubes has been discovered by in-situ transmission electron microscopy (in-situ TEM). By combining intense electron-beam irradiation and heating, structure transformation and 1273 K-sustainable thermal stability of the metal-complexed C32H70N2ZnSO4 nanotubes were directly observed. Associated chemical-bond breaking and self-organization process are considered as main factors for significant structural transformation. The reorganized concentric multi-wall nanotube structure with measured layer-spacing of ~2.7 nm is of such structural rigidity that it exhibits excellent thermal stability. The findings open new opportunities and show great significance of further investigations on diverse molecular-architectures with in-situ TEM platform for both fundamental and technological interests. A general solution method to oriented growth of diverse metal chalcogenides (MCs) has been developed. The oxidation scheme by combining ethylenediamine-chalcogens and hydrazine in alkali solution has been proved to have great advantages on metal-chalcogenides fabrications. By using metal-complex induced oxygenated catalytic reaction, controlled oxidation for the growth of MC nanostructures has been achieved. To our knowledge, the employment of this type of reaction on oriented growth of MC nanostructures is the first demonstrated example. This method is reliable and capable for large scale production. Field-emission measurement results revealed that Ni3S2 and Cu2S nanowire arrays are promising field-emitters. Furthermore, the cathodoluminescence results also show ZnS and Cu2Se to be potentially useful in light emitting devices. The diffusive vapor-transport furnace method for achieving low sulfidation rate at high temperature has been developed for the first time to fabricate sulfur-deficient metal sulfide nanostructures of Ni and Co. Ni3S2 and Co9S8 nanowires can be fabricated in high quality and high yield by combining diffusive vapor transport deposition with CdS nanopowders as sulfidation source. The as-grown nanowires possess properties that have been shown to be promising as interconnects and field emitters.