1Chemical Processes Research Department, Engineering Research Center, University of Isfahan, P.O. Box 81746-73441 Isfahan, I.R. IRAN
2Department of Physics, Faculty of Science, University of Isfahan, P.O. Box 82746-73441 Isfahan, I.R. IRAN
3Department of Biotechnology, Faculty of Advanced Sciences and Technologies, University of Isfahan, P.O. Box 81746-73441 Isfahan, I.R. IRAN
A method for the controllable synthesis of silver nanoparticles based on a complexing agent method was developed. Citric acid was used as a complexing agent. The effect of pH (1.6 to 5.17) on the size and net height (as obtained from XRD analyses) of silver nanoparticles was investigated. The nanoparticles (10 to 40 nm) were characterized using XRD, TEM, SEM, EDX, UV-Vis spectroscopy and TG/DTG instrument. It was found that pH has a significant influence on both size and crystallinity of the nanoparticles. This is due to the effect of pH on the distribution of citrate ion species which in turn affects the size and crystallinity of the nanoparticles. Increasing the pH value enhances the percentage of [citrate3-] ion species which allows lower size and higher crystallinity of the nanoparticles. Thus, we were able to develop a method for the controllable synthesis of nanoparticles based on the pH.
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