Perovskite solar cells have rapidly achieved conversion efficiencies comparable to silicon, driven by their strong light absorption, long carrier diffusion, and tunable chemistry. To enable commercial deployment, however, scalable fabrication methods must produce films with high uniformity over large areas. Blade-coating has emerged as a leading candidate due to its simplicity, adaptability to continuous manufacturing, and high material utilization. Yet, in practice, blade-coated films often show variability in thickness, crystallinity, and defect density due to complex nucleation and growth dynamics. These inconsistencies hinder device output and long-term stability. Due to these challenges, there is a need to deeply investigate how processing parameters influence crystallization to guide large-scale production.
Researchers from Zhejiang University reported a comprehensive review (DOI: 10.1631/jzus.A2500054) in September 2025 in Journal of Zhejiang University–Science A, summarizing the key crystallization control mechanisms in blade-coated perovskite films. The work analyzes how solution chemistry, coating dynamics, environmental factors, and post-treatments collectively determine crystal nucleation, grain evolution, and defect distribution. By integrating recent advances, the study offers a clear framework to optimize film formation for scalable and reproducible device manufacturing.
The study identifies several interconnected factors that define crystallization behavior in blade-coated films. Solvent polarity and evaporation rate strongly influence supersaturation and nucleation timing, where mixed solvent systems help balance solubility and controlled crystal growth. Solution concentration and viscosity affect film thickness and uniformity, with overly high concentration leading to slow evaporation and defect formation, while excessively low concentration limits grain growth. Additives—such as ammonium salts, surfactants, and coordination agents—fine-tune nucleation density, surface passivation, and interface quality, improving grain ordering and stability. Coating parameters, including blade speed, govern whether deposition occurs in evaporation-dominated or Landau-Levich regimes, which directly impacts crystal domain formation. Substrate wettability regulates liquid spreading and suppresses dewetting, while gas-quenching accelerates solvent removal to initiate uniform crystallization. Environmental factors, such as ambient humidity and oxygen exposure, modulate reaction pathways affecting film stability and phase purity. Together, these findings show that achieving high-quality films requires coordinated control of chemical composition, fluid dynamics, and atmospheric conditions during drying.
"The performance and stability of perovskite devices depend heavily on how the film crystallizes during deposition," the authors noted. "Understanding the interplay between solution chemistry, coating process, and environment allows us to systematically tune nucleation and grain growth. This is essential for producing uniform, defect-minimized films, particularly when scaling up from lab cells to large-area photovoltaic modules."
These insights provide a foundation for improving industrial perovskite solar module manufacturing. By optimizing crystallization pathways, manufacturers can achieve higher efficiency, better reproducibility, and longer device lifetimes. The framework also applies to perovskite light-emitting diodes, photodetectors, and tandem solar cells, where film quality is equally critical. Future advances may involve automated coating systems with real-time crystallization monitoring, eco-friendly solvent systems, and new passivation chemistries. Together, these developments could accelerate the commercial transition of perovskite technologies into mainstream clean energy and optoelectronic applications.
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References
DOI
10.1631/jzus.A2500054
Original Source URL
https://doi.org/10.1631/jzus.A2500054
Funding information
This work is supported by the Natural Science Foundation of Zhejiang Province of China (Nos. LR24F040001, LDG25E020001, and LD24E020001), the National Natural Science Foundation of China (No. 62274146), and the Fundamental Research Funds for the Central Universities (No. 226 2022-00200), China.
About Journal of Zhejiang University–Science A
Journal of Zhejiang University–Science A (JZUS-A) is a peer-reviewed academic journal focusing on research in applied physics and engineering. Its scope covers areas such as mechanical and civil engineering, materials science and chemical engineering, environmental science, and energy. The journal is published monthly and is indexed in SCI-E (JCR Q1), Scopus (CiteScore Q1), EI Compendex, and CSCD. It accepts a range of article types, including Research Articles, Reviews, Perspectives, and Correspondence. Currently, Artificial Intelligence in Engineering is one of the most actively promoted and encouraged research directions. JZUS-A operates under a hybrid publishing model, supporting both subscription-based and open access publication.