Modulating crystal growth of formamidinium–caesium perovskites for over 200 cm2 photovoltaic sub-modules

Abstract

Upscalable fabrication of efficient and stable perovskite solar modules is urgently needed for commercialization. Herein, we introduce methylammonium chloride (MACl) additives in the cosolvent system of N-methyl-2-pyrrolidone (NMP) / N,N-dimethylformamide (DMF) to control the formation of intermediate phases during the growth of formamidinium (FA)-cesium (Cs) lead triiodide perovskite films. We achieve high quality films upon drying without the use of antisolvent.By implementing bulk and surface passivation, the champion efficiencies of 24.02% for a smallsized solar cell and 20.5% for a 5 cm × 5 cm solar mini-module on an aperture area of 22.4 cm 2 (geometrical fill factor is ~96%) are achieved by spin-coating. The fully blade-coated perovskite 2 solar sub-module demonstrates a champion efficiency of 15.3% on an aperture area of 205 cm 2 . The solar mini-module exhibits impressive operational stability with a T80 lifetime over 1000 hours at maximum power point tracking (MPPT) under continuous light illumination.

Recent Progress in Large-Area Perovskite Photovoltaic Modules

“…The main solvent favors nucleation and growth by quickly evaporating, while the cosolvent can stabilize the precursor ink (widen the processing window) by strong interaction with the Pb 2+ center. Very recently, Qi and coauthors [109] revealed that N-methyl-2-pyrrolidone can impede the formation of the perovskite-DMF complex intermediates that lead to poor film quality. Combining the introduction of MACl, they achieved an efficiency of 15.3% on a module area of 205 cm 2 .…”

Dimethylammonium Cation-Induced 1D/3D Heterostructure for Efficient and Stable Perovskite Solar Cells

“…To address these issues, various strategies have been attempted, such as additive engineering [ 23 , 24 , 25 , 26 , 27 , 28 ], interfacial modification [ 29 , 30 , 31 , 32 , 33 , 34 ], solvent engineering [ 2 , 35 ] and so on. Among them, the incorporation of one-dimensional (1D) perovskite has drawn great attention due to its unique characteristics in terms of stability [ 36 , 37 , 38 , 39 ].…”

Controlling Phase Transition toward Future Low-Cost and Eco-friendly Printing of Perovskite Solar Cells

“…21 Overall, to obtain efficient, stable scaled-up PSCs, the exploitation of coordination-induced crystallization regulation, and the formation of desirable intermediate phases during the growth of an MA or FA-Cs-based perovskite film can therefore lead to high-performance PSCs. 22 Contributions detailing the transfer of this understanding to large-scale printing are scarce. We start with the description of printing methods currently reported for perovskite PSCs and summarize perovskite phase transition during fabrication.…”

“…Qi and co-workers developed a lead halide-templated crystallization process for printing large-area FA-based perovskite films and minimized the formation of DMF complex intermediates that could induce dendritic crystals . Overall, to obtain efficient, stable scaled-up PSCs, the exploitation of coordination-induced crystallization regulation, and the formation of desirable intermediate phases during the growth of an MA or FA-Cs-based perovskite film can therefore lead to high-performance PSCs …”