Low-photovoltage-loss pringting perovskite solar cells in ambient air through ink synergistic engineering

The uncontrollable large-scare preparation of perovskite in air is currently hindering its photovoltaic industrialization. The internal relationship between the regulation of ink components and the film forming mechanism of perovskite during large-scare preparation is a crucial factor for device performance. Herein, MAAc ionic liquid and Biuret were introduced as the solvent and additive of ink, respectively. Both MAAc and Biuret can independently influence the crystallization process of perovskite and this ink synergistic engineering can accurately regulate the crystallization process and improve the quality of bar-coated perovskite films at reduced process temperatures. We achieved the highest efficiency of 20.62% on a small-area device with improved stability, and an efficiency of 16.51% on a micro-module with an area of 14.8 cm². This ink synergistic engineering with low temperature preparation process is expected to promote the industrialization of perovskite solar cells. In addition, our research on the crystallization process provides guidance for the development of novel coating and printing techniques for perovskite materials.