Innovation Sphere


  • Alexander Hains



Project TitleTFB:TPDSi2 Interfacial Layer As A PEDOT:PSS Replacement in Organic Photovoltaic Cells
Track Code2007-121
Short Description

Northwestern researchers have developed a new interfacial hole transport/electron-blocking layer for organic photovoltaics.

#energy #solar #materials #photovoltaic


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. 

TagsENERGY: solar, MATERIALS: photovoltaic
Posted DateSep 3, 2014 1:58 PM


Alexander Hains


Tobin Marks* 

Alexander Hains 


• Organic photovoltaics 

• Solar cells 


• Increased power conversion efficiency 
• Enhanced device stability 
• Retains robust ITO adhesion 

• Eliminates use of PEDOT:PSS


IP Status

Issued US Patent No. 7,888,593

Contact Information

Zach Brown, PhD

Invention Associate
(p) 847-491-4629