| Surface plasmon resonance of metallic nanoparticles has attracted much attention in the past few decades due to its tremendous impact on many photo-chemical and photophysical processes of molecules. Many important applications including molecular sensing, catalysis, nanolithography and near field optical microscopy utilize the phenomenon. We investigated the influence of surface plasmon resonance of nanotextured silver films on the radiative decay processes of molecular systems. The photoluminescence intensity of dye molecules was enhanced more than an order of magnitude under certain circumstances and we used a photophysical model to interpret the enhancement in terms of absorption enhancement and increased radiative decay rate caused by molecule-plasmon interactions. This thesis also demonstrates extensive studies on the molecule-metal distance dependence of photoluminescence enhancement and the spectral changes of molecular emission and excitation spectra caused by the interaction with metallic nanoparticles. Our work elucidates the optimal conditions under which the most intense photoluminescence can be achieved by using surface plasmon resonance enhancement. The photoluminescence enhancement studies can be applied to organic electronic devices such as light-emitting diodes (OLED) and organic photovoltaic cells. Preliminary results on plasmonic effects in devices are presented at the end of the thesis, and possible improvement options will be discussed. |
