| The research presented in this thesis has been developed to examine the relationship between the CdSe nanoparticle surface and the myriad opto-electronic properties. The motivation for reducing the dimensions of a semiconductor material to the nanometer length scale is to take advantage of the quantum confinement of charge carriers and tune the opto-electronic properties. Reducing the size to the nanometer scale, however, also introduces the influence of surface interactions, normally insignificant in a bulk semiconductor. In many cases, surface interactions compete with intrinsic properties and reduce or alter the benefits that motivate nanomaterials development. A more complete understanding of this relationship is necessary in order to obtain truly tunable opto-electronic materials.; Towards this end surface modification, synthetic methods, and various spectroscopic techniques have been employed to examine the ground and excited state properties of CdSe nanoparticles. First, nanoparticle surface modification with a series of electron-donating materials in general, and n-butylamine specifically, has proven a useful technique in monitoring the spectroscopic changes related to the nanoparticle surface.; Next, the preparation of very small CdSe nanoparticles that are essentially all surface makes it possible to magnify the relationship between surface and intrinsic properties to such a limit that the surface even controls the intrinsic properties. Throughout, steady-state and time-resolved techniques such as fluorescence spectroscopy, hyper-Rayleigh scattering, and ultrafast transient absorption spectroscopy are employed as spectroscopic means to study a chemical system, the nanoparticle surface, that is difficult at best to examine otherwise. |
