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

Abstract

Silver nanostructures have been synthesized via a microwave-assisted polyol method by adding sodium sulfide (Na(2)S) into the solution. An interesting morphology evolution can be observed by adjusting the concentration of Na(2)S and the heating power. It is found that the ideal concentration of Na(2)S is 31.25-500 microM for the fast reduction of Ag(+) at 300 W under optimal conditions for producing monodispersed silver nanocubes. When the heating power is increased to 400 W, 62.5-250 microM is the ideal concentration of Na(2)S for the synthesis of silver nanocubes. On increasing the concentration of Na(2)S (>500 microM), a mixture of silver nanowires, nanocubes, bipyramids, and irregular/quasispherical particles is synthesized at 300 and 400 W. In particular, an increase in the concentration of Na(2)S to 750 microM at 400 W leads to the production of a quantity of silver nanowires. In addition, silver nanocubes with controllable sizes can be obtained by changing the concentration of Na(2)S and the heating power. Compared to traditional wet-chemical methods, this method has the advantage of a marked decrease in reaction time to 3.5 min. Finally, our work provides a simple strategy for fabricating silver nanostructures with controllable morphologies and sizes.