Sanchez, S.; Hua, X.; Phung, N.; Steiner, U.; Abate, A.: Flash Infrared Annealing for Antisolvent-Free Highly Efficient Perovskite Solar Cells. Advanced Energy Materials 8 (2018), p. 1702915/1-7

Organic-inorganic perovskites have demonstrated an impressive potential for the design of the next generation of solar cells. Perovskite solar cells (PSCs) are currently considered for scaling up and commercialisation. Many of the lab-scale preparation methods are however challenging to scale up or are environmentally unfriendly. The highest efficient PSCs are currently prepared using the antisolvent process, which utilises a significant amount of an organic solvent to induce perovskite crystallisation in a thin film. An antisolvent-free method is developed in this work using flash infrared annealing (FIRA) to prepare methylammonium lead iodide (MAPbI3) PSCs with a record stabilised power conversion efficiency of 18.3%. With an irradiation time of fewer than 2 s, FIRA enables the coating of glass and plastic substrates with pinhole-free perovskite films that exhibit micrometre-size crystalline domains. This work discusses the FIRA-induced crystallisation mechanism and unveils the main parameters controlling the film morphology. The replacement of the antisolvent method and the larger crystalline domains resulting from flash annealing make FIRA a highly promising approach for the scale-up of PSC manufacture.