Tuning structural isomers of phenylenediammonium to afford efficient and stable perovskite solar cells and modules

Abstract

Organic halide salt passivation is considered to be an essential strategy to reduce defects in state-of-the-art perovskite solar cells (PSCs). This strategy, however, suffers from the inevitable formation of in-plane favored two-dimensional (2D) perovskite layers with impaired charge transport, especially under thermal conditions, impeding photovoltaic performance and device scale-up. To overcome this limitation, we studied the energy barrier of 2D perovskite formation from ortho-, meta- and para-isomers of (phenylene)di(ethylammonium) iodide (PDEAI2) that were designed for tailored defect passivation. Treatment with the most sterically hindered ortho-isomer not only prevents the formation of surficial 2D perovskite film, even at elevated temperatures, but also maximizes the passivation effect on both shallow- and deep-level defects. The ensuing PSCs achieve an efficiency of 23.9% with long-term operational stability (over 1000 h). Importantly, a record efficiency of 21.4% for the perovskite module with an active area of 26 cm2 was achieved.

Highly Efficient and Stable CsPbTh3 (Th = I, Br, Cl) Perovskite Solar Cells by Combinational Passivation Strategy

“…Furthermore, the two peaks located at 286.0 eV in C1s and 400.3 eV in N1s (Figure 2c ) are attributed to the GA group, combined with the TGA (Figure S4b,c , Supporting Information), indicating that GA cation and GCA additive exist in CsPbTh 3 film. [ 31 , 40 , 41 ] Notably, as shown in Figure 2d and Figure S5 (Supporting Information), the peak positions of Pb4f, Cs3d, and I3d shift to higher binding energy after coincorporation of GA cation, Ac anion, and GCA, likely due to increased formation energy. [ 39 , 42 ] These results are mainly attributed to the GA with six H bonds partially substituting Cs, which can reduce the H—I distance and suppress iodide ion diffusion.…”

Crystal Growth Regulation of 2D/3D Perovskite Films for Solar Cells with Both High Efficiency and Stability

“…[22] Due to the abundant and inevitable defects generated during film fabrication, the quality of the solution-processed perovskite films play a very important role for their photovoltaic properties and device stability. Although some excellent works have been done to improve the PCE and stability by developing different organic spacers, [19][20][21][22][23][24] the crystal nucleation and growth mechanism of 2D/3D perovskite is still not very clear and is largely unexplored. Moreover, the development of efficient crystal growth regulation strategies and understanding the crystallization kinetics in 2D/3D perovskite films are the path to high performance PSCs for future commercial application.In this work, we demonstrate the fabrication of high-quality 2D/3D hybrid perovskite by crystal growth regulation with 2D (NpMA) 2 PbI 4 perovskite.…”

A Bionic Interface to Suppress the Coffee‐Ring Effect for Reliable and Flexible Perovskite Modules with a Near‐90% Yield Rate

“…High‐quality perovskite film is usually related to the appropriate crystallization kinetics. [ 47 ] In order to clearly demonstrate the origin of favorable morphology and good crystallinity, LaMer model ( Figure a) is applied to describe the crystallization kinetics process of perovskite solution on different substrates. Typically, three stages are comprised in the classical LaMer model, stage I: the process from initial state to gradually reaches the supersaturated concentration ( C s ) but still below the lowest concentration to nucleation of perovskite solution, stage II: nucleation begins when the concentration of perovskite solution exceeds the minimum nucleation concentration ( C nu , min ) and stage III: crystal growth after nucleation finishes, at the moment the concentration of perovskite solution is between C numin and C s .…”