Perovskite solar cells in N-I-P structure with four slot-die-coated layers

Abstract

The fabrication of perovskite solar cells in an N-I-P structure with compact titanium dioxide blocking, mesoporous titanium dioxide scaffold, single-step perovskite and hole-transport layers deposited using the slot-die coating technique is reported. Devices on fluorine-doped tin oxide-coated glass substrates with evaporated gold top contacts and four slot-die-coated layers are demonstrated, and best cells reach stabilized power conversion efficiencies of 7%. This work demonstrates the suitability of slot-die coating for the production of layers within this perovskite solar cell stack and the potential to transfer to large area and roll-to-roll manufacturing processes.

Coated and Printed Perovskites for Photovoltaic Applications

“…[62] The drying and crystallization in blade-coated perovskite thin-films is controlled by substrate temperature, gas quenching, solvent quenching approaches, and vacuuminduced crystallization. [66] In summary, blade-coated PSCs demonstrated PCEs exceeding 20% for small-area solar cells and >14% for laboratory-scale PV modules (57 cm 2 , aperture area). [60,61] Alternatively, for slot-die coating, dry air or N 2 -streams are often employed to accelerate the solvent evaporation and for gas quenching in order to induce a rapid crystallization of the perovskite thin film.…”

“…[62] This allowed very rapid crystallization dynamics (<1 s) that led to more uniaxially oriented perovskite grains (fewer grain boundaries in the blocking transport in the vertical direction). [62] In addition, several groups developed allslot-die-coated devices, [59,[65][66][67][68] the best solar cells reaching up to 16% in stable power output efficiency, [59] and a combination of the both coating techniques. [62] The drying and crystallization in blade-coated perovskite thin-films is controlled by substrate temperature, gas quenching, solvent quenching approaches, and vacuuminduced crystallization.…”

“…This led to fully coated PSCs with several perovskite absorbers, i.e., MAPbI 3 (18.2% stabilized PCE) or wide-bandgap FA 0.125 MA 0.875 PbI 2 Br (1.71 eV, 13.9% initial PCE). [62,69] Up to date, not only hole transport layers (HTLs) like the polymers PEDOT:PSS [52,58,70,71] (poly(3,4-ethylenedioxythiophene):(polystyrene sulphonate)), P3HT [65,72] (poly(3-hexyl thiophene)), and PTAA [64] or small molecules like Spiro-OMeTAD (2,2′,7,7′-tetrakis(N,N′-di-pmethoxy phenylamine)-9,9′-spirobifluorene) [66,67] and Bifluo-OMeTAD, [58,67] but also electron transport layers (ETLs) like the fullerenes C 60 [52,56] and PCBM [52,56,69] ([6,6]-phenyl-C 61 -butyric acid methyl ester) and dispersed inorganic metal oxide nanoparticles like NiO x , [56] ZnO, [58,65,67,71] SnO, [59,62,68] or TiO 2 have been successfully deposited by blade coating and slot-die coating. In most cases, elevated substrate temperatures between 40 °C and 165 °C are used for blade coating.…”

Scalable Deposition Methods for Large‐area Production of Perovskite Thin Films

“…2019, 2, 119-145 geometry, web speeds, and fluid feeding rate. [74] Morphology of perovskite films deposited by a two-step slotdie process appears to be similar to the spin-coated films, as seen in Figure 8 (left), thereby showing that both methods yield similar results. [67] Slot-die coating has traditionally been a popular process in the organic PV community and in general is a popular process for non-viscous and low boiling point chemistries due to the possibility of a fully enclosed environment until deposition.…”

“…Mater. [69] The published reports describe the sequential two-step slot-die [70][71][72] and single-step slot-diecoated perovskite layers [71,[73][74][75][76][77][78][79] and fully slot-die-coated heterostructures. Coating properties depend on the wet film thickness, chemistry, and stable microfluidic boundary conditions affected by the geometry.…”