Zelena sinteza koloidnog srebra kemijskim taloženjem pomoću različitih prirodnih reducensa

In this study, the synthesis of colloidal silver with trisodium citrate dihydrate and ascorbic acid was performed as appropriate reducing agents. Based on the obtained UV-Vis peaks, the size of the colloidal particles was estimated and it was concluded which conditions were most suitable for synthesis with the appropriate reducing agent Standard solutions of 0.001 M AgNO 3 and 0.002 M NaBH 4 were prepared, as well as solutions of silver nitrate and trisodium citrate dihydrate solutions at concentrations of 0,010 M, 0,016 M, 0,004 M. The synthesis was carried at 95 °C, with stirring. Silver nitrate and ascorbic acid solutions were prepared at concentrations of 0,010 M, 0,020 M, 0,040 M, and synthesis was carried out at room temperature, with stirring, and at 50 °C. The quality of colloidal silver is evaluated based on the intensity of the Tyndall effect, and the absorbance of the colloids obtained is determined by a UV - Vis spectrophotometer. The test results confirmed the successful use of trisodium citrate dihydrate and ascorbic acid as reducing agents for the synthesis of colloidal silver. The colloidal silver synthesized by sodium borohydride had an estimated particle size of about 14 nm, while the colloidal silver synthesized using ascorbic acid corresponded to a particle size of 14 to 35 nm. On the basis of the intensity of the Tyndall effect, it was shown that better synthesis results were obtained with heating at 50 °C for ascorbic acid, while the synthesis with trisodium citrate dihydrate produced a small amount of colloidal silver because the synthesis was not completely complete. .