A research team led by Prof. GE Ziyi and Associate Prof. SONG Wei from the Ningbo Institute of Materials Technology and Engineering (NIMTE) of the Chinese Academy of Sciences, in collaboration with researchers from Taiyuan University of Technology, has developed a scalable method for fabricating high-performance flexible perovskite solar cells (PSCs) that combine high efficiency and strong mechanical durability.

The findings were recently published in Energy & Environmental Science.

Flexible PSCs show promise as portable power supplies for wearable electronics and soft robotics. However, their large-scale production remains challenging: the uneven deposition of perovskite on hydrophobic self-assembled monolayers (SAMs) frequently results in pinholes and low-quality films over large areas.

To address this issue, the team developed an amphiphilic cross-linkable monomer named TBA. This "smart" molecule contains a hydrophilic boronic acid group that improves the wettability and adhesion of perovskite ink on hydrophobic substrates, ensuring uniform, pinhole-free films even in large-scale manufacturing.

During thermal annealing, the TBA monomer undergoes in-situ ring-opening polymerization, forming an elastic poly (TBA) network inside the perovskite film. This structure serves a dual purpose: it acts as "chemical glue" to passivate defects and as a "mechanical buffer" to reduce internal residual stress.

The TBA-modified flexible PSCs achieved a power conversion efficiency (PCE) of 24.95% along with high operational stability. Furthermore, the devices maintained 90% of their initial PCE after 10,000 bending cycles and 1,000 hours of continuous operation, demonstrating exceptional durability.

The team also fabricated a 10.24 cm² large-area flexible perovskite solar module incorporating TBA. The module delivered a high PCE of 20.38%, verifying the scalability of the developed strategy.

This work provides a new approach to addressing the wetting and mechanical bottlenecks in the large-scale manufacturing of flexible perovskite electronic devices.

This research was supported by the National Key Research and Development Program of China, the National Natural Science Foundation of China, and other funding sources.