From Nano- to Micrometer Scale: The Role of Antisolvent Treatment on High Performance Perovskite Solar Cells

Abstract

To date, antisolvent treatment has become one of the most important means to fabricate high efficiency perovskite solar cells (PSCs); however, the few reported antisolvents have not been analyzed on a uniform platform, and there is hitherto no clear reasoning in the choice of antisolvents toward high performance PSCs. Here, we study the role of the antisolvents in the nucleation kinetics of perovskite solutions and their residual influence on perovskite crystal growth, film formation, and device performance. Through X-ray diffraction analysis on the complicated double mixed perovskite, we qualitatively evaluate the impact of thermal annealing and antisolvent treatment (A.S.T.) on the phase composition and microstructure of the films. By using miscible antisolvents with high boiling point instead of immiscible low boiling point solvents, we obtain homogeneous and almost pinhole-free perovskite films. When using trifluorotoluene (TFT) to replace toluene and chlorobenzene as a novel antisolvent, we achieve a power conversion efficiency (PCE) of 20.3% under optimized device fabrication conditions with a composite perovskite as active layer. The conclusions from this study should assist in establishing reproducible fabrication processes and finding better antisolvent candidates for perovskite solar cells.

Bismuth‐Based Perovskite‐Inspired Solar Cells: In Situ Diagnostics Reveal Similarities and Differences in the Film Formation of Bismuth‐ and Lead‐Based Films

“…Based on these results, we conclude that the major effect of CB dripping is to induce the nucleation of the MA 3 Bi 2 I 9 phase directly from the ink, which in turn solidifies the MA 3 Bi 2 I 9 layer during solution casting. This has been shown to be due to the solubility of GBL and DMSO solvents in CB, which helps their rapid extraction from the solution‐cast film . In contrast, the as‐cast film remains partially solvated with DMSO and GBL, which take much longer to leave, thanks in part to interactions with the solute and their low vapor pressure.…”

Recent Advances in Metal Halide‐Based Perovskite Light‐Emitting Diodes

“…Paek et al. used toluene as an antisolvent whereas chlorobenzene was chosen as antisolvent by Xiao et al . Cho et al.…”

Anti-Solvent Crystallization Strategies for Highly Efficient Perovskite Solar Cells

“…We should also notice here that DE produced significantly lower PCEs when compared to rival CB and TL. Finally, the authors suggested a good trick to see whether an antisolvent is good or bad: one injects the anti-solvent in a vial containing the precursor solution; the formation of the perovskite crystal (brown-blackish precipitate) can be a promising sign for high efficiencies (Figure 11b) [70].…”