**Abstract**

Due to the promising properties of semiconducting polymers they have attracted wide spread interest. During the last decade we have worked on a smart chemistry approach to these substrates and organometallic compounds with special focus on design, synthesis and characterization of materials that could be used in photovoltaic devices. In these materials, one of the most important aspects is high absorbance in the UV-Vis spectrum as a necessary characteristic for high conversion rates of light to electric energy. We were able to show that this can be achieved introducing certain functional groups as, e.g., NO2-moieties. Another important aspect is the interaction with the buffer layers that also form part of the whole photovoltaic device. Here we show that a double layer of CuI/MoO3 increased the energy yield for a large variety of organic substrates along with related results from other leading groups reported in literature.

**Keywords:** polymers, photovoltaics, buffer layer
