Enhancing Efficiency of Organic Solar Cells with Alkyl Diamines Doped PEDOT: PSS

Poly(3,4-ethylenedioxythiophene): poly(styrene-sulfonate) (PEDOT: PSS) has been the most popular conductive polymer as a hole transport material in organic solar cells (OSCs). Modification of PEDOT: PSS can improve its various properties to realize high performance in OSCs. The conductivity of PEDOT: PSS is an essential factor in determining device performance. In this work, PEDOT: PSS-BA, PEDOT: PSS-HA, and PEDOT: PSS-OA are prepared via facile doping of corresponding alkyl diamines into PEDOT: PSS, considering the amino ion can interact with redundant sulfonic acid groups of PSS. All the modified products exhibit enhanced conductivities due to their more ordered molecular packing comparing PEDOT: PSS. Using PTQ10 and m-BTP-PhC6 as the binary active layer, the OSC devices based on PEDOT: PSS-BA yield a superior power conversion efficiency of 18.44%, which ranks as one of the highest values in the binary OSCs.