The increase in global energy demand leads to development of alternative energy sources. One of the most important sources of alternative energy is solar energy. Nowadays, the maximum efficiency of single p-n junction of solar cells is around 26% for GaAs. However, the technology and the materials are too expensive till now. Another possibility to reduce the price of solar cell is to use hybrid solar cells. On the other hand, the efficiency of these solar cells is lower in comparison with inorganic solar cells. Application of nanotechnology in this type of solar cells will essentially increase the solar cell efficiency. Because at quantum confinement effect conditions, for example, the increase of semiconductor band gap takes place. Synthesis of molecular-inorganic semiconductor hybrid nanostructures with various structural organization and studies of their optoelectronic properties in order to control relevant characteristics of these systems is the main issue of the research. Studies of stationary fluorescence spectra and fluorescence quenching kinetic of Si wafer with nano-micro cone (Fig.1), MEH-PPV layer and Si/SiO2/MEH-PPV composite have shown that the fluorescence quenching of MEH-PPV layer is explained by energy transfer from MEH-PPV layer to the SiO2 layer. This process probably can be explained by the optical way energy transfer or electron-hole charge transfer between these layers. In the same time, the fluorescence quenching of MEH-PPV/SiO2/Si composite can be explained by excitons dissociation in p-n hetero junction due to presence of internal electric field. These studies will help to understand and improve the performance of nanoscale hybrid photodetectors and photovoltaic components, based on polymers, semiconductor nanostructures and other type of organic- inorganic hybrids.