A random copolymer based on dithienothiophene and diketopyrrolopyrrole units for high performance organic solar cells

摘要

A random donor-acceptor semiconducting copolymer based on diketopyrrolopyrrole as the acceptor unit and dithienothiophene as the donor unit has been synthesized and characterized. Preliminary studies of BHJ solar cells based on this polymer with PC_(70)BM showed a high PCE of above 5% under 100 mW cm~(-2) AM1.5 solar illumination. The dramatic growing demand for energy throughout the world has placed great emphasis on the exploration of new energy sources. Harvesting energy directly from sunlight using photovoltaic cells is recognized as an important and environment-friendly solution to the growing energy crisis. Compared to commercial inorganic solar cells, polymer solar cells (PSCs) have attracted considerable interest in recent years due to their unprecedented advantages of low cost, easy fabrication and processing, light weight, and compatibility with large-scale flexible substrates.