Bismuth-doped Tungsten Oxide Powder Preparation

Tungsten oxide (WO₃) is a kind of functional material, which has been widely studied in photochromic and gas-chromic fields. It has a wide range of applications in the field of photocatalysis and gas sensors. Through the study of bismuth doped tungsten oxide, it is found that the reflectivity of the material to near infrared is more than 95%.

However, at present, the production method of this material is not suitable for industrial production, and the prepared powder has the characteristics of uneven particle size, easy agglomeration and high cost. In order to overcome the shortcomings of the existing technology, some researchers have proposed a preparation method of bismuth-doped tungsten oxide powder. The prepared powder has uniform particle size and is not easy to agglomerate. The specific steps of the scheme are as follows:

The first step is to dissolve bismuth chloride and potassium tungstate respectively, and tungsten salt is prepared into tungstic acid solution by ion exchange resin.

Step 2, tungstic acid and bismuth salt were mixed in the reaction solvent for 1 hour according to the weight ratio of 1:0.02 to obtain hydrothermal reaction precursor.

Step 3: Add dilute hydrochloric acid to adjust the pH value of precursor solution 4.5;

Step 4: Put the precursor with good pH value into the closed hydrothermal reactor with stirring, and react continuously for 6 hours at 150 ℃.

Fifth step, the precipitate of step four reaction is washed repeatedly, dried at 100 for 8 hours, crushed at 5000rpm for 10 minutes, and calcined at 400 for 4 hours in argon atmosphere to obtain the near infrared high reflection powder of bismuth doped tungsten oxide.

The preparation method has the advantages of simple process and easy purchase of equipment, and is suitable for large-scale industrial production. The obtained bismuth-doped tungsten oxide powders have small particle size, narrow particle size distribution, difficult to agglomerate, good stability, and 95% barrier efficiency to near infrared. They have excellent photocatalytic and gas-sensitive properties.

• < Prev
• Next >