Sequential Ultrasonic Spray‐Coating Planar Three Layers for 1 cm² Active Area Inverted Perovskite Solar Cells

Abstract

The sequential deposition of a NiOx hole‐transporting layer, one‐step CH3NH3PbI3 perovskite absorber, and blended electron‐transporting layer that comprises [6,6]‐phenyl‐C61‐butyric acid methyl ester (PCBM) and PNDI(2OD)T2 via automated ultrasonic spray‐coating technique is demonstrated in air for planar inverted p–i–n solution‐processed perovskite solar cells. Films fabricated via laboratory‐sale spin‐coating and industrially compatible spray‐coating process, respectively, are compared with each other to optimize both the film‐coating quality and corresponding device performance. This is validated by the photovoltaic performance of prototype devices with three spray‐coated layers with the active area of 1 × 1 cm2. The champion cells achieve a power conversion efficiency of 10.09%, which is one of the highest efficiencies obtained from fully spray‐processed large‐area perovskite solar cells thus far. Furthermore, these results reinforce the feasibility of the spray‐coating methodology for the fabrication of multilayers within perovskite solar cells stack and low‐cost route toward upscaling the manufacturing alternatives to spin coating.

Development of Spray-Coated Perovskite Solar Cells

“…Perovskite spray deposition is further complicated by the necessity of controlling the crystallization of the perovskite film as the precursor solution dries . Indeed, if nucleation and crystal growth are not carefully managed during the crystalline intermediate and perovskite film formation processes, the perovskite is often characterized by a rough surface composed of large (≈ 100 μm) crystallites, − ,− which are detrimental to both PSC device performance and stability. When fabricating PSCs by spin coating, it is common practice to drip an antisolvent onto the wet perovskite film to rapidly displace the primary perovskite solvent (often DMF), creating a supersaturated film without the necessity for heat.…”

Enhanced efficiency and stability of scalable spray-coated perovskite solar cells with ionic liquid additives

“…[8][9][10] Process optimization, which is mainly aimed at accelerating the evaporation of the precursor solvent, [11][12][13][14][15][16] along with rational precursor formulation (i.e., perovskite composition, solvents, and additives), [17][18][19][20][21][22][23][24] have enabled the deposition of high-quality perovskite layers with higher power conversion efficiencies (PCEs) in the photovoltaic devices. In addition, approaches for addressing the various challenges in the spraycoating of all layers of the perovskite solar cells (including charge transport layer or electrode), [25][26][27][28][29] and for module representation 30,31 have been proposed.…”

“…, perovskite composition, solvents, and additives), 17–24 have enabled the deposition of high-quality perovskite layers with higher power conversion efficiencies (PCEs) in the photovoltaic devices. In addition, approaches for addressing the various challenges in the spray-coating of all layers of the perovskite solar cells (including charge transport layer or electrode), 25–29 and for module representation 30,31 have been proposed.…”

One-Step Spray-Coated All-Inorganic CsPbI2Br Perovskite Solar Cells

“…Nevertheless, the best-performing laboratory thin-film cells are fabricated using the current spin-coating method, which is incompatible with large-scale manufacturing and commercialization, and a considerable amount of the precursor materials may be wasted during the process. The development of a scalable perovskite film deposition technology is needed for future perovskite photovoltaic industrialization. − Spray coating, which is suitable as a potential upscaling method, has been commonly used to fabricate films in industrial processes because of its advantageous features of cost-effectiveness, rapid manufacturing, high volume, and high material utilization efficiency. , Recently, several researchers have made some progress in the preparation of perovskite films via the spray-coating method. − In 2014, Lidzey et al developed the pioneering spray-on perovskite solar cells under ambient conditions. The solar cells with a spray-coated hybrid mixed halide perovskite film from the precursor solution containing methylammonium iodide (MAI) and PbCl 2 showed an efficiency of 11.1% .…”