Microwave-assisted polyol synthesis of Ag powders

Silver metal powders were prepared through reduction of AgNO3 in ethylene glycol using. microwave-polyol (M-P) and conventional-polyol (C-P) reactions at 100-200 degreesC. Powders of Ag were rapidly produced by microwave-assisted reaction at temperatures above 160 degreesC. The formation yield of Ag powders from AgNO3 reached 97.8% after treatment for 1.35 min at 140 degreesC and 98.6% after treatment for 23 min at 160 degreesC. Compared to the formation of Ag powders using a C-P reaction, a M-P reaction led to increased rate of formation by 6.5 times at 160 degreesC, 5.2 times at 140 degreesC, and 3 times at 130 degreesC. Silver particles of 0.3-2 mum in diameter were produced using M-P and C-P reactions at 100-120 degreesC. The particle size of Ag powders increased with increasing reaction temperatures and times, and particles strongly aggregated at 160 degreesC using C-P and M-P reactions.