Non-Preheating Processed Quasi-2D Perovskites for Efficient and Stable Solar Cells

Area of Science:

• Materials Science
• Renewable Energy
• Crystallography

Background:

• Hot-casting (HC) is common for orienting quasi-2D perovskite films but struggles with thermal control and reproducibility.
• Substrate thermal homogeneity is critical for consistent device fabrication.

Purpose of the Study:

• To develop a facile and effective non-preheating (NP) film-casting method for highly oriented quasi-2D perovskite films.
• To improve the reproducibility and stability of perovskite solar cells.

Main Methods:

• Partial replacement of butylammonium (BA+) spacers with methylammonium (MA+) cations in quasi-2D perovskites: (BA)2-x(MA)3+xPb4I13.
• Fabrication of perovskite films using both non-preheating (NP) and hot-casting (HC) methods.
• Characterization of film morphology, crystal orientation, and device performance.

Main Results:

• The optimal film composition (x=0.4) yielded highly oriented crystals with dense morphology and uniform grain size using the NP method.
• Non-preheating (NP) processed solar cells achieved 15.44% efficiency, while hot-casting (HC) processed cells reached 16.29%.
• The NP method demonstrated superior performance reproducibility and improved moisture stability compared to HC and unsubstituted films.

Conclusions:

• The non-preheating (NP) film-casting method is a viable alternative to hot-casting for fabricating highly oriented quasi-2D perovskite films.
• Optimized cation mixing enhances crystal orientation, morphology, and device performance.
• The NP method offers improved reproducibility and stability for perovskite solar cell fabrication.