Convenient, rapid synthesis of silver nanocubes and nanowires via a microwave-assistedpolyol method

Abstract

Silver nanostructures have been synthesized via a microwave-assisted polyol method by adding sodiumsulfide (Na2S) into the solution. An interesting morphology evolution can be observed by adjusting the concentrationof Na2S and the heating power. It is found that the ideal concentration ofNa2S is 31.25–500 µM for the fastreduction of Ag+ at 300 W under optimal conditions for producing monodispersed silvernanocubes. When the heating power is increased to 400 W, 62.5–250 µM is the idealconcentration of Na2S for the synthesis of silver nanocubes. On increasing the concentration ofNa2S (>500 µM), a mixture of silver nanowires, nanocubes, bipyramids, and irregular/quasisphericalparticles is synthesized at 300 and 400 W. In particular, an increase in the concentration ofNa2S to750 µM at 400 W leads to the production of a quantity of silver nanowires. In addition, silvernanocubes with controllable sizes can be obtained by changing the concentration ofNa2S and the heating power. Compared to traditional wet-chemical methods, this method hasthe advantage of a marked decrease in reaction time to 3.5 min. Finally, our work provides asimple strategy for fabricating silver nanostructures with controllable morphologies andsizes.