Kinematic analysis of nanocomposite optical absorption of Ag/Ag2O prepared by a green method

In this report, silver and silver oxide nanocomposites are synthesized using a green method at different concentrations of silver nitrate. In this method, coelomic yellow liquid extracted from earthworms has been used as a silver nitrate reduction. The crystal structure of the obtained nanoparticles was analyzed by X-ray diffraction pattern and Rietveld method. The results show that with increasing the concentration of silver nitrate, the size and strain of silver oxide nanoparticles remained unchanged, but the size of silver nanoparticles increased and strain decreased. SEM images show uniform particle distribution, high density, and spherical geometric shape. By measuring and fitting the UV spectra of the nanocomposites, the weight percentage and the absorption peak of each component were determined. Accordingly, with increasing the concentration of silver nitrate, the absorption peak for silver nanoparticles is shifted to the higher wavelengths and for silver oxide nanoparticles is almost constant. Also, the weight percentage of silver oxide remains almost constant, and increases for silver nanoparticles. In the framework of a simple kinematic model, it is shown that its origin can be related to the different reactions speed of conversion of silver nitrate to silver and silver oxide.