Controllable Synthesis of Ag Nanocubes via a Polyol Method

The controllable synthesis of uniform silver nanocubes with high purity is pivotal for the fundamental study of self-assembly and further research on the hollow nanostructures, gold nanocages for instance. Here, Ag nanocubes of different sizes were synthesized by an improved polyol method. With addition of HCl solution, Ag nanocubes with size about 100 nm were obtained under an air atmosphere. And Ag nanocubes with size around 50 nm can be produced in a short time under Argon atmosphere with the presence of NaHS instead of HCl. Meanwhile, uniform Ag nanocubes with size larger than 100 nm were also synthesized successfully via adjusting experiment parameters. Results of transmission electron microscopy (TEM) combined with selected area electron diffraction (SAED) show that the Ag nanocubes are single crystalline with six (200) surface plane. In the UV-Vis-NIR optical absorption spectrum, the diple moment resonance absorption peak is changed in the range of 420-500 nm with the increase of Ag nanocubes size.