Alkanethiol mediated release of surface bound nanoparticles fabricated by nanosphere lithography

This work presents an innovative approach to produce monodisperse solution-phase triangular silver nanoparticles with well-controlled geometry. Ag nanotriangles are fabricated by nanosphere lithography (NSL), functionalized with alkanethiol molecules and then released from the substrate into solution. The resulting single isolated nanoparticles are subsequently asymmetrically functionalized with alkanedithiol molecules to form dimer pairs. The optical properties of the Ag nanoparticles have been measured using UV-Vis spectroscopy while their structural properties have been characterized using atomic force microscopy (AFM) and transmission electron microscopy (TEM). Theoretical calculations based on Mie theory and the Discrete Dipole Approximation (DDA) method have been done to interpret the optical properties of the released Ag nanoparticles.