Interfacial modification of hole transport layers for efficient large-area perovskite solar cells achieved via blade-coating

Efficient large-area planar heterojunction (PHJ) perovskite solar cells (PSCs) were successfully developed by adapting a scalable doctor blade printing method under ambient condition. To achieve high-quality perovskite films onto poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) layer, the PEDOT:PSS was modified by adding poly(4-styrenesulfonic acid) (PSSH), which uses the electrostatic interaction between the sulfonyl functional groups in PEDOT:PSS and perovskite precursor ions. The resulting perovskite film on the modified PEDOT:PSS (M-PEDOT:PSS) exhibited excellent uniformity and surface coverage with high crystallinity even for large-area (15 mm x 40 mm) scale. In addition, the power conversion efficiency (PCE) of the printed PSCs was significantly improved from 6% to 10.15% by introducing our M-PEDOT:PSS layer. This finding provides an important guideline to achieve highly efficient PSCs using scalable printing techniques. (C) 2015 Elsevier B.V. All rights reserved.