Fabrication of low-cost and flexible perovskite solar cells by slot-die coating for indoor applications

Abstract

The fast progress of perovskite solar cells (PSCs) in terms of their photovoltaic performance under different lighting conditions, stability, and upscaling demonstrates the great potential of this technology to transit to the industrial scale. In particular, the performance of PSCs under low-light conditions has already surpassed the energy efficiency of the well-established amorphous silicon technology. However, PSC's industrialization will only be possible if the manufacturing process of the whole device is compatible with large-scale mass production. Here, we optimized an experimental procedure for fabricating flexible and low-cost PSCs under ambient atmosphere, low temperature, and high speed using only solution-based deposition techniques that are easy to upscale. An n–i device prepared by slot-die coating of SnO₂ and perovskite layers and blade-coating a carbon electrode layer achieved a power conversion efficiency of 16.5% under 1000 lux and 6.9% under 1 sun. Using a 2D perovskite capping layer to passivate the 3D perovskite's surface defects, the power conversion efficiency increased to 18.6% under 1000 lux and to 7.7% under 1 sun. The 3D and 2D/3D hybrid perovskite devices lost 4% and 23%, respectively, of their initial efficiency after 550 h of operation at maximum power point tracking (MPPT) at 0.25 sun.