Preparation And Formation Mechanism Of Nanometer-Sized Zinc Oxide By Homogeneous Precipitation

It had been briefly summarized about the developmental survey and actuality, fundamental characters, applications and preparing methods of nanometer materials including nanometer zinc oxide in the paper, and the process technology of nanometer powders was thought to be one of important steps in the preparation and application of high property materials, limitations existed in the current preparing methods of nanometer zinc oxide had also been pointed out, and new technicses were bring forward aiming at the problems existed in the preparing methods of sol-gel and precipitation.It had been discussed about the synthesizing scheme of predecessor about diethyl zinc used in the method of sol-gel, problems existed in it also were pointed out. Such factors caused influence to the granularity of zinc oxide powders had been systematically investigated as temperatures and times of hydrolyze reaction, the kinds and amount to be used of exterior dispersant, the value of pH, the Moore ratios of raw materials, the temperatures and times of calcinations, it had been indicated by the results that under the conditions of the Moore ratio of raw materials was 1 to 1.25, the temperature and time of hydrolyzing reaction was 80 C and 4hours respectively, PHSA used as exterior dispersant and the amount of which was 0.35%, the value of pH was 7.0, the predecessor of zinc hydroxid could be prepared out. Under the circumstance of the best calcination technics, the temperature and time of calcination was 700 C and 2.5 hours respectively, nanometer zinc oxide had been prepared. Through such tests as DTA, XRD, BET, TEM, it had been proved that the prepared zinc oxide was hexagonal crystallization, and the granularity was about 80nm.With the method of solution chemistry, it had been explained about the influence of hydrolyzing conditions to the granularity of nanometer zinc oxide. Using the theory of crystal development, the influence of super saturation degree to the granularity of nanometer zinc oxide, and it preferably explained the relationships between the Moore ratios of rawmaterials and the granularity of nanometer zinc oxide.