TFB:TPDSi2 INTERFACIAL LAYER USABLE IN ORGANIC PHOTOVALTAIC CELLS

Novel TFB:TPDSi2 Interfacial Layer with Improved Power Conversion Efficiency for Organic Photovoltaic Cells NU 2007-121 Inventors Tobin Marks* Alexander Hains Abstract Northwestern researchers have developed a new interfacial hole transport/electron-blocking layer for organic photovoltaics. This technology obviates the need for the commonly employed PEDOT:PSS layer and significantly improves the performance of MDMO-PPV:PCBM bulk heterojunction (BHJ) solar cells. While organic photovoltaics (OPV) offer advantages over traditional inorganic photovoltaic cells, including fabrication on lightweight flexible substrates and use of lower cost spin-coating and printing processes, it lacks sufficient power conversion efficiency for commercial use. This invention enhances BHJ solar cell efficiency by addressing several areas critical to device performance. A unique TFB:TPDSi2 blend, spin-coated from an organic solvent and air cured to form a covalently bonded film on ITO provides this function. The cured material is transparent above ~ 400 nm, resists solvent attack in subsequent processing and retains adhesion above 60°C. Importantly, the interlayer components possess aligned energy levels, which permits holes to travel efficiently to the anode while preventing electron leakage. This feature results in a vast improvement in power conversion efficiency. This unique combination of interlayer properties provides a basis for significantly improved BHJ solar cell devices. Applications o Organic photovoltaics o Solar cells Advantages o Increased power conversion efficiency o Enhanced device stability o Retains robust ITO adhesion o Eliminates use of PEDOT:PSS IP Status A patent application has been filed. Marketing Contact Allan E. Nader, Ph.D Licensing Associate (p) (847) 491-4456 (e) a-nader@northwestern.edu