All‐Vapor‐Deposited FACs‐Perovskite Solar Modules with Power Conversion Efficiency of >19%

Abstract One of the key requirements for perovskite solar cells (PSCs) commercialization is using scalable techniques to reproducibly fabricate high‐efficiency PSC modules (PSMs). Although all‐vapor deposition process is significantly attractive to both research and industry field, the demonstration of high efficiency modules has been rarely reported. Here, an all‐vapor deposition technology is presented for the fabrication of PSMs with an active area of 10.0 cm 2 and power conversion efficiencies exceeding 19%. This performance is enabled by the high quality of the chemical vapor‐deposited perovskite films, which are found to be strongly affected by the hole transporting layer. A hole‐transporter based on the (2‐(pyren‐1‐yl)ethyl)phosphonic acid is introduced that sustains optimal kinetics of the vapor‐solid reaction and enables formation of the pinhole‐free perovskite films comprised of grains with a size of ≈1 µm. Apart from conventional PSMs, this all‐vapor‐deposition strategy is also applied to produce semitransparent modules with an efficiency of 17.5%. Moreover, these all‐vapor‐deposited modules retained >85% after 1000 h of continuous operation.