a tio 2 Preparation method of /zns double-layer composite nanotube array

Abstract

The present invention relates to a bi-layer composite nano ZnS method for preparing TiO2 / tube array, - TiO2 is a wide band gap (3.2 eV) semiconductor material, due to its strong oxidizing power, illumination light does not occur after etching, high catalytic activity, the source of wide, non-toxic, etc. has become a more in-depth study of a plurality of photocatalytic material in the relevant art. However, there is still a low quantum efficiency of TiO2 powder particles agglomerate easily deactivated, difficult to recycle and other defects during use. To solve the above problems, to improve the photocatalytic efficiency, typically TiO2 reforming process. The present invention is the use of porous anodic aluminum oxide as a template, the method of assembling the liquid layer, the ZnS nested into TiO2 nanotubes. The resulting two-ply composite of the present invention, nanotubes, greatly increasing the area of ​​contact with the ZnS, TiO2; while both the valence band due to the special structure, improved charge separation rate, increase the photocatalytic efficiency. An array of nanotubes present in the form of readily recovered from the treated sewage to avoid secondary pollution, which has very important applications in the wastewater treatment.

Description

[0001] Technical field: [0002] The invention relates to a method for preparing an inorganic composite nanotube array, in particular to a TiO 2 / ZnS double-layer composite nanotube array preparation method, more specifically, the AAO / TiO 2 nanotube arrays, then on AAO / TiO 2 Array based ZnS embedded in TiO prepared by hydrothermal method 2 Bilayer Composite TiO Inside Nanotubes 2 / ZnS nanotube arrays. The technology belongs to the field of preparation of nanometer materials. [0003] Background technique: [0004] In recent years, industrial wastewater, especially VOCS (Volatile Organic Compounds) produced by petrochemical industry, has an increasing impact on the environment, which has seriously affected the sustainable development of the ecological environment and has aroused widespread concern in the society. With the country's emphasis on sewage discharge standards, the sewage discharge standards are getting higher and higher, prompting enterprises to demand low-cost,...

AI Technical Summary

Problems solved by technology

But TiO 2 There are still the following problems in the process of use: (1) TiO 2 The forbidden band is wide, and it can only absorb short-wavelength light with a wavelength below 385nm. The energy accounts for only 4% of the solar light energy. How to use the visible light and even the infrared light energy, which accounts for more than 45% of the total light energy, is the decisive factor for photocatalytic materials. Whether it can be a prerequisite for large-scale practical application

(2)TiO 2 As a single semiconductor material, the recombination rate of photogenerated electron-hole pairs is also high, and its defects such as low quantum efficiency also limit its use to a certain extent.

(3) Traditional nano-TiO 2 The powder particles are easy to deactivate, so it is not conducive to long-term utilization, poor cycle characteristics, easy to agglomerate and reduce the active reaction surface area, poor adsorption capacity, small particles difficult to recycle and other fatal defects, its application is limited to a certain extent

For TiO 2 / ZnS composite materials, most of which exist in the shape of particles, or in the form of randomly dispersed nanotubes, and most of them are ZnS particles attached to TiO 2 The outer wall of the pipe is difficult to recycle in the sewage treatment, and it is easy to cause secondary pollution

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