In a significant stride towards enhancing the stability and efficiency of perovskite solar cells, researchers have developed a multifunctional interface engineering strategy that addresses key bottlenecks limiting their performance. The study, led by Yonggui Sun of the Hoffmann Institute of Advanced Materials at Shenzhen Polytechnic University, introduces a novel approach to simultaneously tackle metal electrode corrosion and interfacial defects in perovskite solar cells (PSCs), paving the way for broader commercial applications in the energy sector.
The research, published in InfoMat (translated from Chinese as Information of Materials), focuses on incorporating the ionic liquid 1-butylpyridinium tetrafluoroborate (BPYBF4) into the PCBM electron transport layer. This innovative strategy not only mitigates iodine-induced degradation but also passivates interfacial defects and suppresses ion migration. “By coordinating with silver ions, the BF4− anions form a corrosion-resistant layer, while the BPY+ cations react with residual PbI2 at the perovskite surface, inducing the formation of a protective 1D perovskite capping layer,” explains Sun. This dual functionality enhances the overall stability and performance of the solar cells.
One of the most compelling aspects of this research is its broad applicability across different bandgap configurations. The study demonstrates significant efficiency improvements for both normal-bandgap and wide-bandgap PSCs. For instance, the power conversion efficiencies (PCEs) achieved were 22.69% for 1.67 eV and 18.60% (certified at 17.75%) for 1.85 eV, respectively. These advancements are particularly noteworthy given the challenges associated with wide-bandgap PSCs, which are crucial for tandem solar cell configurations.
The phase-transition process during film conversion was systematically investigated, revealing a gradual transformation of residual PbI2 into a protective 1D perovskite structure upon BPYBF4 incorporation. This finding underscores the importance of understanding the underlying mechanisms to optimize device performance. Additionally, the presence of ionized PCBM enhances surface potential alignment, promoting efficient electron extraction and reducing non-radiative recombination losses.
The implications of this research extend beyond single-junction devices. The strategy offers a promising approach for stabilizing perovskite films in tandem configurations, which are essential for achieving higher efficiencies and meeting the growing demand for renewable energy solutions. “This work provides a facile and scalable approach to simultaneously protect the electrode and stabilize the perovskite films,” Sun notes, highlighting the potential for commercial impact.
As the energy sector continues to seek innovative solutions to enhance the efficiency and stability of solar cells, this research represents a significant step forward. By addressing critical issues such as electrode corrosion and interfacial defects, the study opens new avenues for the development of high-performance perovskite solar cells. The findings not only contribute to the scientific community but also offer practical insights for industry stakeholders looking to leverage advanced materials and technologies in their products.
In summary, the research led by Yonggui Sun and his team at Shenzhen Polytechnic University demonstrates a multifunctional interface engineering strategy that enhances the performance and stability of perovskite solar cells. Published in InfoMat, this work highlights the importance of understanding and optimizing interfacial interactions to achieve superior device performance. As the energy sector continues to evolve, such advancements are crucial for driving the adoption of renewable energy technologies and meeting global sustainability goals.