Green Synthesis of ZnO Nanoparticles via Thermal Decomposition of Zn-Complex Achieved from Phenylalanine

In this research, ZnO NPs were synthesized via a green chemistry method using phenylalanine. At the first step, phenylalanine, 5–sulfosalicylaldehyde sodium salt, and zinc acetate dehydrate were separately solved in water. The obtained solutions were then mixed and stirred to appear white sediment. This compound was calcined to synthesis ZnO powder. The STA results showed that phase transformation was accomplished in the temperature range of 400-500 ºC; therefore the firing temperatures were selected as 400 and 500 ºC. Both of the samples consisted of ZnO phase without impurity, whereas peaks intensity and degree of crystallinity increased by increasing the calcination temperature. Microscopic images showed that particle size and image quality were improved by temperature increasing. This phenomenon led to improve the optical properties of the synthesized sample. The absorbance and photoluminescence were intensified by increasing the calcination temperature.