Formamidinium post‐dripping on methylammonium lead iodide to achieve stable and efficient perovskite solar cells

Abstract

Formamidinium iodide (FAI) based perovskite solar cells (PSCs) have now been established as effective PSCs than methylammonium lead iodide perovskite for several years due to their optimal bandgap and high thermal stability.However, the FAI-based PSCs have humidity issues, due to which mixed cation perovskites are getting popular. MAI-based PSCs have better stability against high humidity but low thermal stabilities. Herein, we prepared highly crystallized, efficient, and large-grain size perovskite films via FAI postdripping process. In addition, the most promising structures FAI mixed MAPbI 3 were explored as stable and effective active layers. The post-dripping of FAI solution just after the MAPbI 3 deposition provides a robust longdistance diffusion, long carrier life, and enhanced grain sizes when compared to MAPbI 3 PSCs. Based on the facile way of mixed cation perovskite preparation by post-dripping, the power conversion efficiency (PCE) has risen from 15.24% to 17.52% in comparison with the pristine devices. This results in the best quality and large grain perovskite films which enhanced the PSCs' performance by reducing defect density and regulating the crystallization rate.

Full Life-Cycle Lead Management and Recycling Transparent Conductors for Low-Cost Perovskite Solar Cell

“…Similarly, 475 mg of PbI 2 and 159 mg of MAI were added into the mixed solvent of DMSO (100 μL) and DMF (900 μL) and churned for 2 h at 60 °C to obtain a uniform precursor colloidal solution with the addition of 1.14 mg, 2.28 mg, and 5.70 mg of FAAc in ambient air. Note that introduction of a certain amount of FA into MAPbI 3 perovskite is favorable for improving the stability of MAPbI 3 -based PSCs. , The CsPbI 2 Br precursor solution was spin-coated onto the ITO/SnO 2 substrate via a two-step process at 500 rpm for 5 s and 3000 rpm for 25 s, respectively. Next, the wet all-inorganic film was annealed at 50 °C for 2 min and then 150 °C for 10 min to realize a rapid process of gradient precrystallization.…”

“…Note that introduction of a certain amount of FA into MAPbI 3 perovskite is favorable for improving the stability of MAPbI 3 -based PSCs. 49,50 The CsPbI 2 Br precursor solution was spin-coated onto the ITO/SnO 2 substrate via a two-step process at 500 rpm for 5 s and 3000 rpm for 25 s, respectively. Next, the wet all-inorganic film was annealed at 50 °C for 2 min and then 150 °C for 10 min to realize a rapid process of gradient precrystallization.…”

Mixed‐Halide Inorganic Perovskite Solar Cells: Opportunities and Challenges

“…This limits the further DOI: 10.1002/adom.202301052 development of PSCs. [11][12][13][14] For example, the MAPbI 3 absorber layer decomposes during the annealing of the film at 85 °C in an inert atmosphere. [11][12][13][14][15] The stability of FAPbI 3 films is better than MAPbI 3 when exposed to sunlight.…”

“…[11][12][13][14] For example, the MAPbI 3 absorber layer decomposes during the annealing of the film at 85 °C in an inert atmosphere. [11][12][13][14][15] The stability of FAPbI 3 films is better than MAPbI 3 when exposed to sunlight. [16] Replacing MA with FA can improve the thermal stability of the films and obtain better light absorption and narrower bandgap.…”

Engineering the intermediate adduct phase to control the crystallization of perovskites for efficient and stable perovskite solar cells

“…[6][7][8] Among two widely employed methods, including the onestep anti-solvent method and two-step deposition, the two-step method improves the perovskite morphological properties such as high crystallinity and large grain sizes. [8][9][10][11][12][13][14][15] Still, the control of perovskite composition is a strenuous task. 16 The one-step antisolvent method is generally preferred over the two-step method to enhance the performance of PSCs, but it results in a small grain size.…”