Preparation method of molybdenum-nitrogen-codoped TiO2 granule and application thereof

Abstract

The invention relates to a preparation method of a molybdenum-nitrogen-codoped TiO2 granule and the application thereof. The preparation method comprises the following steps: mixing concentrated hydrofluoric acid and concentrated nitric acid into a precursor solution, adding TiN and MoO3; pouring the solution into a hydrothermal reaction kettle for hydrothermal reaction; performing solid-liquid centrifugal separation on a solid-liquid mixture after the reaction; taking out a solid product; eluting and drying; and grinding the dried product into powder to obtain a finished product. The molybdenum-nitrogen-codoped and (001) crystal face-exposed TiO2 granule prepared by the preparation method, as a photocatalyst, can be used for purifying air or water; the codoped TiO2 granule prepared by the preparation method has an obviously-improved visible light absorbing efficiency and has obvious red shift, effectively inhibits conversion of nitrogen doping into a photocarrier compound center, improves photoinduced electron-hole migration efficiency and much exposure of (001) active surfaces, and enhances photocatalytic performance of visible light. The preparation method is simple in process and easy to control; and the production efficiency is high.

Description

technical field [0001] The invention relates to a method for preparing molybdenum and nitrogen co-doped, (001) highly active crystal face exposed to a large number of TiO 2 Methods and uses of particles. Background technique [0002] Photocatalysis refers to the use of semiconductors to absorb solar energy and convert it into chemical energy to degrade organic matter. This method is efficient and does not cause secondary pollution. It is a new direction for environmental governance, and the key to photocatalytic technology is suitable Catalyst selection and preparation. transition metal oxide TiO 2 It has the advantages of non-toxic and harmless, high catalytic efficiency, good stability, and low cost. It is an ideal photocatalyst material and has great application prospects. But TiO 2 Mainly has 3 disadvantages: 1) TiO 2 (Anatase phase, anatase) has a band gap of 3.2 eV, can only absorb ultraviolet light with a wavelength within 387 nm, and has a low utilization rate...

AI Technical Summary

Problems solved by technology

But TiO 2 Mainly has 3 disadvantages: 1) TiO 2 (Anatase phase, anatase) has a band gap of 3.2 eV, can only absorb ultraviolet light with a wavelength within 387 nm, and has a low utilization rate of natural sunlight; 2) TiO 2 The electron-holes excited by photons in the interior have been recombined in large quantities before migrating to the surface, and there are few widely-generated carriers participating in the photocatalytic reaction; 3) TiO obtained by common methods 2 A large number of exposed crystal planes are low-energy (101) planes, and high-energy (001) planes are less exposed

Currently developed a TiF 4 、TiCl 4 , TiN, TiC and other inorganic titanium sources or organic titanium sources such as tetrabutyl titanate are hydrothermally grown in a hydrofluoric acid (HF) environment to prepare TiO with a large number of (001) crystal planes exposed 2 , but this cannot absorb visible light, and for this TiO 2 It is difficult to do doping, because the introduction of other ions will change the chemical environment of the solution, which is not conducive to the adsorption of fluoride ions, thus hindering the exposed growth of (001) crystal planes

[0010] Based on the above discussion, it can be seen that in the preparation of TiO with high photocatalytic efficiency 2 In the process, to overcome one of its defects will often lead to other problems, especially so far, there has been no literature report that can simultaneously achieve visible light absorption, high photogenerated carrier transfer efficiency, (001) crystal plane exposed TiO 2 Technology and method of controllable preparation

Images