Highly Efficient Nonfullerene Organic Solar Cells With A Self-Doped Water-Soluble Neutral Polyaniline As Hole Transport Layer

Among the various conducting polymers, polyaniline (PANI) has received a great deal of attention due to its low cost, excellent chemical and thermal stabilities, and high electrical conductivity. Herein, a newly designed self-doped water-soluble PANI derivatives-poly (diphenylamine-4-sulfonic acid) (PDAS) is readily prepared and applied as hole extract layer in nonfullerene organic solar cells. PDAS, with satisfactory structural and electrical homogeneity, exhibits high conductivity of 7.75 x 10(-2) S cm(-1), none of acidity (with pH around 7), as well as enhanced work function of 5.43 eV, compared with the well-known poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS). The power conversion efficiency of PDAS-based devices is comparable with that of PEDOT:PSS-based devices with the PM6:BTP-4F-12 as active layer. The successful design of the new self-doped water-soluble conductive polymer and its commercial application potential is demonstrated.