How to Prepare Biscuit Shaped Nano Tungsten Disulfide?

Biscuit shaped nano tungsten disulfide can be prepared by calcining tungsten powder, sulfur powder and K₂HPO₄ salt at the temperature of 500°C. This method is simple, low-cost and suitable for mass production.

Reagents required for the preparation include tungsten powder (the purity is 99.9% and the particle size is from 1 to 2 microns), sulfur powder (the purity is 99.9% and the average particle size is 5.2 microns), analytical pure anhydrous ethanol and analytical pure K₂HPO₄.

There is some equipment needed in the preparation. They are DF-101S thermostatic heating magnetic stirrer, electronic balance, miniature stainless steel reactor, DHG-9055 electrothermal blowing dry box, KSY SCR temperature controller, HZ-D circulating water vacuum pump and KQ-500B ultrasonic cleaner.

Biscuit shaped tungsten disulfide is prepared by the following steps:

Step One: The right amount of anhydrous ethanol is used as dispersion medium. Tungsten powder (the weight is 0.9192 gram), sulfur powder (the weight is 0.3520 gram) and K₂HPO₄ (the weight is 2 grams) are agitated magnetically in a 20 mL covered bottle for 1 h and then stand. The supernatant of the mixture is removed before it is dried for several hours in the electrothermal blowing dry box at 80°C. And by this time, the anhydrous ethanol is completely eliminated.

Step Two: The dried mixture is grinded into powder. Then the powder is transferred to the stainless steel reactor and calcined in it for 3 hours at 500°C. After the natural cooling, the tungsten disulfide powder is prepared.

Step Three: The prepared tungsten disulfide powder is added to NaOH (the mass fraction is 5%) aqueous solution at 60°C and reacted in it for 30 minutes so as to remove the remaining sulfur powder. Then the mixture is washed with distilled water, filtered and dried in the oven at 100°C step by step before the pure nano tungsten disulfide is successfully prepared.

Tungsten disulfide is formed slowly in the molten K₂HPO₄, so its morphology and size can be effectively controlled. Biscuit shaped nano tungsten disulfide can be successfully prepared with a thickness of 50 nanometers. This is a simple and low-cost preparation method that is suitable for the mass production.

• < Prev
• Next >