Perovskite solar cells and large area modules (100 cm2) based on an air flow-assisted PbI2 blade coating deposition process

• Blade coating deposition for perovskite solar cells with efficiency up to 13.3%.
• Study of PbI2 and perovskite layer morphology with SEM and photocurrent maps (LBIC).
• Laser patterning of the PbI2 layer with a CO2 laser.
• High efficiency (10.3%) blade coated perovskite module on 10.1 cm2 active area.
• 100 cm2 module, obtained with blade coating deposition of perovskite and HTM layers.

The present work focuses on research into alternative and more scalable processes for organometal halide perovskite layer deposition. We compare solar cells fabricated by sequential step deposition of the perovskite layer, where the PbI2 film is deposited using either blade or spin coating. By controlling the crystallization of the PbI2 with air flow, a highly compact layer was obtained with both techniques. The final perovskite structure was then obtained by dipping the substrates in a methylammonium iodide solution. The study and the consequent optimization of the blade coating process and the dipping time, led us to achieve 10 mm2 solar cells with a maximum efficiency of 13.3% and an average efficiency of 12.1%. To prove the scalability of the process, series connected modules were fabricated containing blade coated PbI2 films. The films were laser patterned with a CO2 laser before being dipped in the methylamine iodide solution. A module efficiency of 10.4% was obtained for a 10.1 cm2 active area. An efficiency of 4.3% was measured for a module area of 100 cm2.