In the first reporting period (01/11/2023 – 08/02/2025), HEPAFLEX achieved progress across materials development, device engineering, and environmental safety.
In WP1, photonic annealing (FIRA) was optimized for perovskite films with uniform grains and reduced defects. Flexible substrates (PET, PEN, polyimide) and FA/Cs-based compositions were validated. Ferrocene-based SAMs with different anchoring groups were developed as hole transport layers; PDI-based materials were tested as low-temperature, water-processable ETL alternatives. Green synthesis of MAI, FAI, PbI2, and PbBr2 was scaled and characterized; 15 PILs were created for ink formulation. Large-area coatings (blade, slot-die, inkjet) under ambient conditions enabled fast perovskite crystallization (<1 min) on PET. Full stacks with PEDOT and screen-printed carbon reached >10% efficiency in small areas, with minimal loss in 5 cm² modules.
In WP2, early stability testing showed improved results with refined encapsulation. Devices stored in nitrogen retained 60% of initial PCE after 1000 hours; minimodules kept 80% outdoors after 10 days. Impedance spectroscopy, PLQY, and ideality factor analysis were implemented to monitor degradation. Guanidinium and acetamidinium doping enhanced photoluminescence recovery under damage. Encapsulation using parylene and dual-layer acrylate/PDMS demonstrated good Pb containment.
In WP3, PILs and green solvents enabled removal of perovskite and carbon layers. PbI2, Cs⁺, FA⁺, and Au were recovered; gold purification is being refined. Cation exchange resins showed success in capturing Pb. Toxicity monitoring was initiated, and SSbD templates shared. Inventories for LCA, LCC, and SLCA were compiled.
