Question

The goal is to make silver nanoprisms--not spheres, rods, or any other shape. It turns out that nanoprisms are the most stable shape for silver nanoparticles. What chemical principle could you invoke to insure that you make primarily the desired, stable shape (nanoprisms) and get rid of the others? HINT: Think about what chemical processes are going on to make Ag0 nanoparticles. Then how could you destroy the less stable shapes? Which of the following chemicals could you use to achieve that goal? KBr, H2O2, NaBH4, sodium citrate.

Answer 1

By Chemical reduction we make primarily the desired, stable shape (nanoprisms) and get rid of the others.

These reducing agents reduce Ag+ and lead to the formation of metallic silver (Ag⁰), which is followed by agglomeration into oligomeric clusters. These clusters eventually lead to the formation of metallic colloidal silver particles .

Control over the size of the silver nanoprisms is achieved when   silver ions are reduced by sodiumborohydride in the presence of citrate and peroxide as stabilizing and shape-directing agents.