Researchers at Huaqiao University in China have successfully created a perovskite solar cell achieving an impressive 26.39% efficiency, which retains 95.4% of its original efficiency after 1,100 hours of operation, according to reports by PV Magazine.
The primary challenge in perovskite solar cells has been their instability, largely due to ion migration within the cell. To address this issue, the scientists introduced a hole-selective intermediate layer that effectively prevents ion diffusion.
Innovative Design for Enhanced Stability
"We have demonstrated that designing internal barriers to block ion diffusion between layers is crucial for improving the lifetime of perovskite solar cells," the researchers explained. The hole-selective interlayer is composed of an ultrathin polymer material known as PDTBT2T-FTBDT (D18). The team applied this interlayer by spin-coating a hot solution of chlorobenzene (CB) D18 onto the perovskite film, resulting in the formation of a dense membrane.
Superior Performance Compared to Common Polymers
Testing revealed that the D18 interlayer outperformed commonly used polymers like P3HT and PTAA. The resulting solar cell, with an area of 0.12 cm² under standard lighting conditions, achieved:
- Energy Conversion Efficiency: 26.39%
- Open-Circuit Voltage: 1.185 V
- Short-Circuit Current: 26.54 mA cm⁻²
- Fill Factor: 83.92%
Additionally, the cell maintained 95.4% of its initial efficiency after 1,100 hours of operation, marking it as the most stable high-efficiency perovskite solar cell currently available.
Significance of the D18 Polymer Interlayer
"We have shown that the introduction of a D18 polymer interlayer can effectively block the diffusion of ions between layers inside perovskite solar cells while maintaining highly efficient hole transport. This leads to a significant increase in the stability of cells with a certified efficiency of over 26%," the study's authors emphasized.
Comparative Advances in Solar Technology
As a reminder, the Chinese company Trina Solar has previously developed fully passivated n-type heterojunction (HJT) solar modules with an efficiency of 25.44%, setting a new efficiency record. Furthermore, scientists from the Helmholtz Institute for Renewable Energy in Erlangen-Nuremberg have discovered new organic molecules that can further enhance the efficiency of perovskite solar cells.
This breakthrough by Huaqiao University represents a significant advancement in the field of solar energy, promising more durable and efficient perovskite solar cells for the future.
