Slot Die Coating Boosts Perovskite Solar Cell Efficiency

• Unlocking the future of solar energy, researchers achieve 19.17% efficiency with revolutionary slot die coating for perovskite films, paving the way for stable and efficient solar solutions.

Researchers at South Korea's Jeonbuk National University have successfully utilized slot die coating (SDC) to produce high-quality perovskite films, achieving a solar cell efficiency of 19.17%. This method enhanced the roughness of the hole transport layer (HTL), significantly improving surface wettability, which resulted in fewer defects such as bubbles and pinholes. A lab-sized module derived from this method demonstrated a slightly lower efficiency of 17.42%.

The study highlighted the combination of nickel oxide (NiOx) and the self-assembled monolayer Me-4PACz as effective for the HTL, overcoming previous wettability challenges. The SDC process not only facilitated uniform layer formation but also minimized energy losses at the interface, leading to superior charge transport properties. The devices exhibited over 85% of their initial efficiency after more than 2,000 hours, indicating strong stability. Researchers believe their findings could significantly advance the commercial viability of perovskite solar cells.

How does slot die coating enhance perovskite solar cell efficiency and stability?

Enhancing Perovskite Solar Cell Efficiency and Stability through Slot Die Coating

• Improved Film Uniformity: Slot die coating provides a consistent and uniform application of perovskite materials, reducing variability between different areas of the cell. This uniformity is crucial for maximizing active surface area, leading to better light absorption and overall efficiency.
• Control over Thickness: The SDC technique allows for precise control over the thickness of the coated layer, which is vital for optimizing the light absorption properties of the perovskite material. A well-controlled layer can influence the absorption spectrum and enhance the conversion efficiencies.
• Minimized Surface Defects: By enhancing the wettability of the hole transport layer (HTL) and creating smoother surfaces, the SDC method significantly reduces defects such as bubbles and pinholes. Fewer defects lead to lower non-radiative recombination losses, thus improving overall efficiency.
• Enhanced Charge Transport: The combination of materials like nickel oxide (NiOx) with self-assembled monolayers in the HTL helps to create efficient pathways for charge transport. Improved charge mobility ensures better collection of photogenerated charge carriers, enhancing the power conversion efficiency.
• Reduced Energy Losses: The slot die coating process minimizes energy losses at the interfaces of different layers. This reduction in energy losses, particularly at the exciton dissociation interfaces, results in increased efficiency for the solar cells.
• Long-Term Stability: The findings from this research indicate that perovskite solar cells produced using SDC can retain over 85% of their initial efficiency after extended periods (more than 2,000 hours). This suggests improved resistance to degradation and environmental factors, making them more reliable for long-term applications.
• Scalability: The SDC technique is amenable to mass production, which is essential for commercial solar cell applications. Its ability to produce high-quality films at scale positions it as a valuable method in the competitive renewable energy market.
• Cost-Effectiveness: The slot die coating technique potentially reduces the manufacturing costs associated with the production of perovskite solar cells. Lower costs can foster greater adoption and integration of these technologies into mainstream energy solutions.
• Potential for Innovative Materials: The flexibility of the SDC method allows for the exploration of new materials and compositions for both the perovskite layer and HTL, paving the way for future enhancements in efficiency and stability.
• Contribution to Sustainability: By optimizing the performance and stability of perovskite solar cells, the use of slot die coating can significantly contribute to sustainable energy solutions, helping to meet global renewable energy targets and reduce reliance on fossil fuels.