Sequential Molecule-Doped Hole Conductor to Achieve >23% Perovskite Solar Cells with 3000-hour Operational Stability.

Even though the hole transport layer (HTL) based on solution-processed doped Spiro-OMeTAD has been extremely popular and effective for its remarkable performance in n-i-p perovskite solar cells (PSCs), its scalable application is still being held back by poor chemical stability and unsatisfied scalability. Essentially, the volatile components and hygroscopic nature of ionic salts often cause morphological deformation that deteriorate both device efficiency and stability. Herein, we strategically introduce a simple and effective molecular implantation assisted sequential doping (MISD) approach to modulate spatial doping uniformity of organic films and fabricate all evaporated Spiro-OMeTAD layer in which phase-segregation free HTL is achieved accompanied with high molecular density, uniform doping composition, and superior optoelectronic characteristics. The resultant MISD-based devices attain a record power conversion efficiency (PCE) of 23.4% which represents the highest reported value among all the PSCs with evaporated HTLs. Simultaneously, the unencapsulated devices realize considerably enhanced stability by maintaining over 90% of its initial PCEs in air for 5200 h and after working at maximum power point under illumination for 3000 h. This method provides a facile way to fabricate robust and reliable HTLs towards developing efficient and stable perovskite solar cells. This article is protected by copyright. All rights reserved.