Multilayer Blade‐Coating Fabrication of Methylammonium‐Free Perovskite Photovoltaic Modules with 66 cm² Active Area

Abstract

Solar cells based on hybrid organic/inorganic perovskites have shown an astonishing efficiency development in the past years, having peaked in power conversion efficiencies of >25% for small‐area single‐junction devices. To pave the way for future commercialization, however, high power conversion efficiencies also have to be demonstrated on areas multiple orders of magnitude larger. Herein, methylammonium‐free perovskite photovoltaic modules with an active area of 66 cm2 are presented. All functional layers processable from solution are deposited by blade coating without the use of an antisolvent, demonstrating the feasibility of this approach for large‐area module fabrication. The coating process is analyzed in detail and a model based on the Landau–Levich problem is developed for the blade‐coating setup. The perovskite crystallinity can be improved by the addition of lead(II) thiocyanate, which results in increased crystallite size as judged by Williamson–Hall's analysis of X‐ray diffraction data and corresponding scanning electron microscopy images. The homogeneity of the final modules is investigated with dark lock‐in thermography and electroluminescence imaging, indicating only few shunts in the module area. Modules are made up of 15 serially interconnected solar cells and reveal a stabilized efficiency of 12.6% under maximum power point tracking.

Recent Developments in Upscalable Printing Techniques for Perovskite Solar Cells

“…small molecules like Spiro-OMeTAD [119][120][121][122] and NiO x , [123][124][125] but also electron transport layers (ETLs) like the fullerenes C 60 , [112] PCBM, [112,124,126,127] ZnO, [128] SnO 2 , [129][130][131][132] and TiO 2 . [133] Recently, Lee et al developed a new donor-acceptor-donor type HTL with 4-dicyanomethylene-4H-cyclopenta[2,1-b;3,4b']dithiophene (diCN-CPDT) core tethered with two bis(alkoxy) diphenylaminocarbazole periphery groups (Figure 3b) and applied it for the fabrication of fully printed perovskite solar cell using a thermal assisted blade-coating technique.…”

“…[ 109 ] Apart from these physical and chemical modification approaches, several other approaches such as solvent engineering, adding, and doping strategies have also been summarized well in the previous reports. [ 24,113 ] Furthermore, several groups have successfully developed blade‐coating technique for printing of not only HTLs like the polymers PEDOT:PSS, [ 112,114–116 ] and PTAA [ 117,118 ] or small molecules like Spiro‐OMeTAD [ 119–122 ] and NiO x , [ 123–125 ] but also electron transport layers (ETLs) like the fullerenes C 60 , [ 112 ] PCBM, [ 112,124,126,127 ] ZnO, [ 128 ] SnO 2 , [ 129–132 ] and TiO 2 . [ 133 ] Recently, Lee et al.…”

Monolithic Perovskite–Perovskite–Silicon Triple-Junction Tandem Solar Cell with an Efficiency of over 20%

“…They have band gaps of 1.55 and 1.90 eV, respectively, which are as close to ideal band gaps as practically possible while still retaining high performance. For hole transports, a self-assembled monolayer (SAM) based on carbazole with methyl substitution (2-(3,6-dimethoxy-9 H -carbazol-9-yl)­ethyl)­phosphonic acid, MeO-2PACz) is employed for the middle-band-gap cell, which has been demonstrated to be effective for hole extractions from mid-band-gap perovskites. For the top cell, a MeO-2PACz/sputtered NiO x is developed as the hole transport layer stack which is used for the first time for a triple-junction tandem cell.…”

Molecular Engineering of Fluorene‐Based Hole‐Transporting Materials for Efficient Perovskite Solar Cells

“…Starting from the first publication by A. Kojima et al back in 2009, [ 1 ] PCSs have reached 25.5% efficiency of the single‐junction devices, [ 2 ] and over 29% efficiency of the silicon/perovskite tandem devices. [ 3 ] The advantage of the PSCs over traditional solar cell technologies lays in the vast variety of the available deposition techniques, such as solution‐processing (e.g., inject printing, [ 4 ] slot die, [ 5 ] blade coating, [ 6 ] etc.) and vapor deposition.…”