Flexible perovskite solar panels are emerging as a candidate for lightweight, bendable solar photovoltaics, but maintaining high efficiency while maintaining long-term stability and low costs remains difficult. A research team from the Institute of Metal Research of the Chinese Academy of Sciences and Zhengzhou University reports flexible perovskite solar panels with an energy conversion efficiency of more than 20 percent that can tolerate mechanical and environmental stress. The work focuses on single-walled carbon nanotube films used as window electrodes in scalable flexible perovskite solar panels.
The team shows that single-walled carbon nanotube films are hydrophobic, which helps block moisture and slow the breakdown of the perovskite layer, improving device stability. Their mechanical flexibility and relatively low material costs make these carbon nanotube electrodes suitable for application in distributed energy generation, integrated into buildings and infrastructure that support reduced carbon emissions.
A central step in the research is the treatment of the carbon nanotube network with sulfuric acid. The acid treatment increases the electrical conductivity of the nanotube films and promotes interaction with nickel oxide to form a compact NiSO4 – NiOx layer at the interface.
This boundary layer improves charge transfer between the perovskite absorber and the hole transport material, allowing indium tin oxide-free perovskite solar cells to achieve energy conversion efficiency of more than 24 percent, while flexible devices maintain approximately 23 percent. At high temperatures, high humidity and continuous sunlight for a month, these devices retained more than 95 percent of their original efficiency.
The researchers also fabricated flexible, indium tin oxide-free module-scale devices using a simple and scalable process, achieving greater than 20 percent efficiency with improved stability and bending performance. The work further demonstrates that single-walled carbon nanotube films can be produced on meter-scale substrates via a chemical vapor deposition-based roll-to-roll process, which supports the production of carbon nanotube-based perovskite modules on a larger scale.
Together, the findings indicate that sulfuric acid-treated carbon nanotube electrodes, manufactured using established acid processing routes, can improve both the performance and durability of flexible perovskite solar technologies.
Research report:Integrating SWCNT to Bridge the Stability Gap in Scalable and Manufacturable Flexible Perovskite Solar Panels
