Breakthrough Lattice Strain Boosts Perovskite Solar Cell Efficiency

• Breakthrough in solar tech: Researchers enhance perovskite cells with lattice strain, achieving 93.5% efficiency limit and improved stability, paving the way for more durable, efficient solar energy solutions.

Researchers from EPFL, National University of Singapore, and Nanjing University of Aeronautics and Astronautics have developed a method using lattice strain to enhance the stability and efficiency of perovskite solar cells. By locking in rubidium and controlling atomic structure distortion, they achieved 93.5% of the theoretical efficiency limit, reducing non-radiative recombination and energy loss. This approach addresses phase segregation issues in wide-bandgap materials, which absorb high-energy light but often degrade over time.

The team fine-tuned the material's composition through rapid heating and controlled cooling, preventing unwanted secondary phases and integrating rubidium within the crystal structure. X-ray scans, NMR, and computer simulations validated their method, showing that lattice strain stabilizes rubidium. Adding chloride ions balanced element size differences, enhancing ion distribution and material stability. The new material achieved an open-circuit voltage of 1.30 volts and a significant boost in photoluminescence quantum yield, indicating efficient sunlight-to-electricity conversion with minimal energy waste.

How does lattice strain improve perovskite solar cell efficiency and stability?

• Lattice strain helps to lock in rubidium ions within the perovskite structure, preventing them from migrating and causing instability.
• It reduces non-radiative recombination by minimizing defects and imperfections in the crystal lattice, leading to higher efficiency.
• The controlled distortion of the atomic structure through lattice strain enhances the material's ability to absorb and convert sunlight efficiently.
• By addressing phase segregation issues, lattice strain ensures that the perovskite material maintains its structural integrity over time, improving long-term stability.
• The method of rapid heating and controlled cooling, combined with lattice strain, prevents the formation of unwanted secondary phases that can degrade performance.
• Lattice strain, along with the integration of rubidium and chloride ions, balances the size differences of elements, leading to a more uniform ion distribution and enhanced material stability.
• The approach results in a higher open-circuit voltage and improved photoluminescence quantum yield, indicating a more efficient conversion of sunlight to electricity with reduced energy loss.