Combined Vacuum Evaporation and Solution Process for High Efficiency Large-Area Perovskite Solar Cells with Exceptional Reproducibility.

Organic inorganic hybrid perovskites have exhibited outstanding performances in perovskite solar cells (PSCs). However, the complex solution chemistry of perovskites precursors renders it difficult to prepare large-area devices in a reproducible way, which is a prerequisite for the technology to make an impact beyond lab scale. Vacuum processing, instead, is an established technology for large-scale coating of thin films. However, with respect to the hybrid perovskites it is highly challenging due to the high vapor pressure of the organic ammonium halide. In this work, we combine vacuum evaporation of lead iodide and solution processing of organic ammonium halide to produce large-area homogeneous perovskite films with large grains in a highly reproducible way. The resulting PSCs achieved a power conversion efficiency (PCE) of 24.3% (certified 23.9%) on small area (0.10 cm 2 ), 24.0% (certified 23.7%) on large area (1 cm 2 ) and 20.0% for minimodule (16 cm 2 ), and maintained 90% of its initial efficiency after 1000 hours 1-sun operation. The vacuum evaporation prevents advert environmental effects on lead halide formation, guarantees a reproducible fabrication of high-quality large-area perovskite films, which opens a promising way for large scale fabrication of perovskite optoelectronics. This article is protected by copyright. All rights reserved.