چكيده به لاتين
In this study, cobalt-doped zinc oxide nanoparticles were synthesized as an inorganic nanopigment by polyol method, which is a versatile, cheap and environmentally friendly method. Upon identifying the effective factors on the synthesis, the experimental design and statistical analysis were done based on the Taguchi method. We found that in order to achieve smaller average crystallite size and higher crystallinity, ethylene glycol should be used as a reaction medium in the optimal process for the production of cobalt-doped zinc oxide nanopigment. Ethylene glycol, which is known as a solvent equivalent to water, has the ability to withstand temperatures higher than 100°C, so it is possible to create a higher crystallinity by synthesizing at a higher temperature than synthesizing by solvothermal method in an aqueous medium. Furthermore, this polyol can act as a reducing agent, which is one of the factors affecting the reaction kinetics and controlling the growth of particles. This results in better formation of particles and more effective precipitation.
Other factors such as the molar ratio of cobalt nitrate to zinc acetate, reaction time, molar ratio of water and sodium hydroxile to zinc acetate, the type of surfactant and its molar ratio to zinc acetate were investigated at the specified levels and a sample with an average crystallite size of 10 nm and the wurtzite and hexagonal structure of NanoPigment included by14% amorphous phase was synthesized. Furthermore, the effect of the effective factors in the synthesis on the colorimetric Properties was investigated, so it is possible to produce nanopigments with the desired colorimetric Properties by determining and controlling the effective factors on the synthesis. Furthermore, the synthesized inorganic nanopigments were subjected to colorimetry as optimal samples in terms of the average crystallite size and the percentage of amorphous phase, and their colorimetric coordinates were subjected to statistical analysis to express the specific color as well as. according to the colour physics, colorimetric coordinates are only for expressing colour Properties and distinguishing between colours, so there are no optimal points for colorimetric coordinates, but the ability of nanopigment production with desirable colorimetric coordinates for each specific Application is very important. generally, decreasing the percentage of amorphous phase result in increases the brightness of the colour and reduces the impurity, the better placement of cobalt particles in the zinc oxide structure by diffusion and causes the increase of the brightness coordinate and the inclination of the a* coordinate to the values that represent more green as well as.
