The picture shows the SEM photos of titanium dioxide gel particles obtained by different dosage of tetrabutyl titanate, in which the molar ratio of tetrabutyl titanate to ethyl acetoacetate is 1.0. It can be seen from the figure that the amount of tetrabn-butyl titanate has a great influence on the morphology of the obtained powder. When n-octanol was not added as solvent in the oil phase solution, that is, the volume ratio of n-octanol to tetrabutyl titanate was 0.0, the obtained powder showed two kinds of microscopic morphology, including spherical particles and irregular flaky particles. When the volume ratio of n-octanol to tetra-n-butyl titanate was 2.0, the obtained powder showed regular spherical structure. When the volume ratio of the two increases to 8.0, the agglomeration is obtained. As shown in the figure, the agglomeration is formed by the bonding of spherical particles. When n-octanol was not added, the oil phase solution was composed of tetrabn-butyl titanate and ethyl acetoacetate, so the concentration of tetrabn-butyl titanate in the oil phase solution was high, so the reaction rate at the oil/water interface was still high, although its hydrolysis rate was inhibited by ethyl acetoacetate. When the oil phase solution is added to the water phase to form an oil-like drop, the oil/water interface gels to form a solid spherical shell, while the inside of the sphere is still a liquid phase. If the sphere has a large volume, it may be destroyed under high-speed shear, while if the sphere has a small volume, it may still maintain a spherical structure under high-speed shear. Therefore, the flaky powder in the obtained powder may come from the destroyed spherical shell. The spherical powder may come from semi-cured spheres that are not destroyed under high-speed shear. However, when the concentration of tetrabutyl titanate is too low, the strength of the gel ball formed after gel curing is too low, so that in the subsequent collection process, the force deformation and even the bond into a block.
