Breakthrough in Stable, Efficient Wide-Bandgap Perovskite Solar Cells

• Breakthrough in solar tech: New method boosts wide-bandgap perovskite solar cells to 23.3% efficiency, promising scalable, stable, and sustainable energy solutions.

Researchers from the University of North Carolina at Chapel Hill and Hong Kong Polytechnic University have developed a method to improve wide-bandgap (WBG) perovskite solar cells, addressing issues like photovoltage loss, poor stability, and fabrication challenges. By incorporating a reductive methylhydrazinium cation, they reduced defect density and suppressed iodide oxidation and halide demixing, allowing for scalable production of efficient and stable WBG solar cells in ambient air.

The enhanced WBG perovskite solar cells achieved a power conversion efficiency (PCE) of 23.3% with a low voltage loss of 0.37 V. Mini modules demonstrated a stabilized PCE of 19.8% over a 25 cm² area, maintaining 94% of initial PCE after 700 hours under continuous light at 55 ± 5 °C. This advancement offers a promising path for sustainable solar energy harvesting.

How does the new method improve efficiency and stability of WBG perovskite solar cells?

• Reduced Defect Density: The incorporation of the reductive methylhydrazinium cation effectively reduces defect density in the perovskite layer, leading to improved charge carrier mobility and reduced recombination losses.
• Suppressed Iodide Oxidation: By preventing iodide oxidation, the method enhances the chemical stability of the perovskite material, which is crucial for maintaining efficiency over time.
• Halide Demixing Prevention: The approach addresses halide demixing, a common issue that can lead to phase segregation and reduced device performance, thereby ensuring uniformity in the material composition.
• Scalable Production: The method allows for the fabrication of WBG perovskite solar cells in ambient air, facilitating scalable production processes that are more cost-effective and environmentally friendly.
• High Power Conversion Efficiency (PCE): Achieving a PCE of 23.3% with a low voltage loss indicates a significant improvement in energy conversion efficiency, making these cells more competitive with traditional silicon-based solar cells.
• Enhanced Stability: The solar cells maintain 94% of their initial PCE after 700 hours of continuous light exposure at elevated temperatures, demonstrating excellent long-term stability.
• Mini Module Performance: The mini modules show a stabilized PCE of 19.8% over a 25 cm² area, highlighting the potential for practical application in larger-scale solar panels.
• Sustainable Energy Harvesting: This advancement supports the development of more sustainable and efficient solar energy solutions, contributing to the broader adoption of renewable energy technologies.