Effect of WO3 concentration in ammonium tungstate solution

 

As it can be seen from Figure 1, the bulk density of the APT increases with WO3 concentration in solution decreases. When WO3 concentration is reduced to a certain extent, the bulk density of APT has no obvious change. It shows that when the WO3 concentration in solution is high, the supersaturation is high. Nucleation is fast, so it’s not easy for crystalline particles to grow. When the WO3 concentration in solution is low, oversaturation of the evaporation process does not change significantly in the solution, the oversaturation is low so it helps nuclei to grow. However, when the WO3 concentration in solution is too low, the oversaturation is too low, less chance of contact between the solute and molecule nuclei, affecting the growth of grains.