Synergistic effects of buffer layer processing additives for enhanced hole carrier selectivity in inverted Organic Photovoltaics
Journal
Organic Electronics
Date Issued
November 2013
Abstract
Solution based inverted Organic Photovoltaic (OPVs) usually use Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) derivatives combined with pristine processing additives as hole selective contact on top of the hydrophobic conjugated polymer:fullerene active layer. In this study, PEDOT:PSS based hole selective contact is treated with two different boiling point additives, 2,5,8,11-tetramethyl-6-dodecyn-5,8-diol ethoxylate (Dynol) and Zonyl FS-300 fluorosurfactant (Zonyl). Although corresponding inverted OPVs using the above PEDOT:PSS:Additives show similar power conversion efficiency (PCE) values, the mechanisms of their implementation on inverted OPV operation are not identical. By understanding the synergistic effects of PEDOT:PSS processing additives on the hole selectivity of inverted OPVs we demonstrate a novel combination of PEDOT:PSS additives mixture as an effective route to further increase the hole selectivity, reliability andpower conversion efficiency of inverted OPVs.