| One-dimensional nanomaterials, such as nanowire, nanotube and nanobelt, have attracted increasing attention due to their novel optical, electronic, magnetic and chemical properties. Various kinds of methods have been developed to prepare one-dimensional nanomaterials. Template synthesis is proved to be very effective. In this thesis, electrochemical template synthesis, based on porous anodic aluminum oxide (AAO) membranes, has been used to fabricate several kinds of one-dimensional nanomaterials.(1) Metal Pt, Ag, Ni, Ru, Pt-Ru alloy and Pt-WO3 nanowires have been fabricated by electrochemical deposition in the AAO templates with thin silver membrane as conductive substrate. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray energy-dispersion analysis (EDAX) and electron diffraction (ED) were employed to investigate the morphology, atomic composition and crystal structure of the as-prepared nanowires.Pt nanowires have been prepared by electrochemical template method. Nanowires began to grow from the bottom of the AAO templates. The columnar structure of the nanowires corresponds to the structure of the nano-scale pores of the templates.Direct current electrodeposition was applied for the first time to fabricate Ag nanowires within the pores of AAO templates. The Ag nanowires are smooth, in single crystal state, about 200 nm in diameter and tens of micrometers in length.Ni nanowire arrays have been fabricated by electrodeposition within the pores of AAO templates. The morphology of Ni nanowire arrays was obtained for the first time. Ni nanowires are uniform in diameter and length, and are parallel to each other. This property makes the materials have large fractional surface area. In the case of catalysts, the nanowire arrays with large surface area would give a high catalytic effect. The ability to fabricate well-defined nanowire arrays represents an important step towards the development of a new kind of effective electrooxidation materials.The preparation of Ru nanowires has not been reported. Electrochemical template method was applied to fabricate Ru nanowires. The as-fabricated nanowires are 20 nm in diameter and are polycrystallites.Pt-Ru alloy nanowires have been prepared successfully by electrochemical template method. The obtained nanowires are 20 nm in diameter and are parallel to each other. The atomic ratio of Pt to Ru of the Pt-Ru alloy nanowires is 5 : 1. It is possible that the well-ordered Pt-Ru alloy nanowire arrays can be used as electrocatalyst of direct methanol fuel cell.Pt-WO3 nanowire arrays have been prepared by electrochemical deposition within the pores of AAO template. The as-prepared nanowires are 50 nm in diameter. The weight ratio and atomic ratio of Pt to W are 19.6 :1 and 18.5 : 1 respectively.The above results show that electrochemical template method is very feasible and general to fabricate nanowires.(2) Pt nanotube arrays have been fabricated successfully for the first time by electrodepositing Pt into the pores of AAO membranes. The pore walls were not derivatized by molecular anchors, but were equipped with nanoarchitectured silver nano-ring array electrodes in the bottom of the AAO templates. The so-prepared Pt nanotubes are fcc polycrystallites and have well-defined outer diameters, largely determined by pore diameters of the AAO templates. The wall thickness of nanotubes is controlled by the deposition time. The key point of this novel method is that the Ag nano-ring array electrodes act as the substrate for Pt growth, which accomplishes the simplicity in operation and generality in fabricating other metals.(3) It has been found for the first time that Au nanobelts can be formed in the pores of AAO templates by electrodepositing. This is the third kind of one-dimensional materials except for nanowire and nanotube that can be fabricated by electrochemical depositing method used thick membranes with one-dimensional nanochannels as templates. It can be deduced from the morphology of the as-prepared Au nanobelts that...
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