Gold nanowires with mixed optional arrangement of various close-packed structures and their preparation method and application

Abstract

The invention provides gold nanowires with mixed optional arrangement of various close-packed structures and their preparation method and application. The preparation method comprises the steps of 1)dispersing a gold precursor, a copper salt and an etching agent in oleylamine to obtain a reaction liquid; 2) allowing the reaction liquid of step 1) to react at 100-210 DEG C, centrifuging after reaction, and washing to obtain the gold nanowires with mixed optional arrangement of various close-packed structures. The gold nanowires prepared by the preparation method have an average diameter of 13.2 nanometers and can be supported on activated carbon, silicon dioxide, titanium dioxide or alumina to act as a catalyst to catalyze dehydrogenative coupling reaction and electrocatalytic reduction ofcarbon dioxide. The gold nanowires have high-density defect structure, and exhibits enhanced catalytic performance in catalytic reaction, particularly in dehydrogenative coupling reaction of silane and water (and hydroxy compounds).

Description

technical field [0001] The invention belongs to the field of nanometer science, and relates to a gold nanowire with a variety of close-packed structures mixed and arranged arbitrarily, as well as a preparation method and application thereof. Background technique [0002] Since Haruta et al. discovered in 1989 that gold nanoparticles have high low-temperature carbon monoxide catalytic oxidation performance and their unique humidity enhancement effect, nano-gold catalysts have gradually become the darling of scientists and industries. They are widely used in environmental pollution, electrochemical biosensors, etc. fields have a wide range of applications. The reserves of gold in the earth's crust are scarce and the distribution is extremely scattered. These two factors make the price of gold very expensive. Therefore, how to improve the activity, selectivity, and stability of gold catalysts is of great significance to economic development, environmental protection, and resou...

AI Technical Summary

Problems solved by technology

However, in terms of the synthesis and preparation of the phase structure, the existing methods are very limited. Except for the conventional face-centered cubic structure, only Hua Zhang et al. successfully synthesized tetragonal gold nanoflakes with a 2H hexagonal close-packed structure, and a 4H hexagonal close-packed structure. Gold nanoribbons and 4H and face-centered cubic composite stacked gold nanorods, etc.

[0004] So far, the above work still has the following deficiencies: first, the methods for preparing gold nanocrystals with various stacked structures are limited, and the experimental cycle is very long (often more than 10 hours), making it difficult to prepare in large quantities; second, the preparation has The defect structure, especially the gold nanocrystal structure with high density defects, is difficult to achieve large-scale preparation; third, there is no method so far to prepare gold nanocrystals with three or more different stacking structures at the same time.

Fourth, most of the gold nanocrystals with non-face-centered cubic stacking structures obtained so far have poor stability and are prone to phase transitions during catalytic reactions.

These reasons obviously limit the practical application of highly active nano-gold catalysts.

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