Photochemically grown silver nanoparticles with wavelength-controlled size and shape

We use light to transform a colloidal solution of spherical silver nanoparticles into larger nanoparticles of a different shape. The particle size and shape can be controlled by choosing the wavelength(s) of light used to drive the photochemical growth. These findings suggest a new way of thinking about growth of nanoparticles in solution and show the exciting possibility that light can be used as a major control parameter in metallic nanoparticle growth reactions.