Brian Woodworth

Advances in Plexcore active layer technology systems for organic photovoltaics: roof-top and accelerated lifetime analysis of high performance organic photovoltaic cells

We report NREL-certified efficiencies and initial lifetime data for organic photovoltaic (OPV) cells based on Plexcore PV photoactive layer and Plexcore HTL-OPV hole transport layer technology. Plexcore PV-F3, a photoactive layer OPV ink, was certified in a single-layer OPV cell at the National Renewable Energy Laboratory (NREL) at 5.4%, which represents the highest official mark for a single-layer organic solar cell. We have fabricated and measured P3HT:PCBM solar cells with a peak efficiency of 4.4% and typical efficiencies of 3 - 4% (internal, NREL-calibrated measurement) with P3HT manufactured at Plextronics by the Grignard Metathesis (GRIM) method. Outdoor and accelerated lifetime testing of these devices is reported. Both Plexcore PV-F3 and P3HT:PCBM-based OPV cells exhibit >750 hours of outdoor roof-top, non-accelerated lifetime with less than 8% loss in initial efficiency for both active layer systems when exposed continuously to the climate of Western Pennsylvania. These devices are continuously being tested to date. Accelerated testing using a high-intensity (1000W) metal-halide lamp affords shorter lifetimes; however, the true acceleration factor is still to be determined.

32.1: Invited Paper: Plexcore®OC for HIL Applications in OLED Lighting and Display

Plexcore® OC, an aqueous hole injection layer (HIL), is a tunable ink platform that offers a wide range of work functions (−5.3 to − 5.7 eV by AC2) and resistivities (100 to >10,000 Ohm-cm) to extend device lifetime and performance with various emitter technologies. Other properties include low acid content, excellent transparency in the visible spectrum (>90%), tunable viscosity (6–30 cP) for various coating applications and low surface roughness (Rq < 10 nm) to minimize defects. Plexcore® OC is demonstrated to provide improved stability to de-doping phenomena, even at fields of 60 kV/cm. Additionally, the relative voltage stability using Plexcore® OC in a typical POLED has been demonstrated to be less than 0.5V over the life of the device.