Scientists at Wuhan University of Technology in China have built a polymer solar cell that achieves 19.1% efficiency while retaining 97% of its performance after 2,000 hours in air. The research team solved a long-standing problem with polymer chain entanglement that previously limited both efficiency and lifetime.
Researchers at Wuhan University of Technology fabricated a polymer solar cell that reached 19.1% power conversion efficiency. The device maintained 97% of its initial performance after 2,000 hours of operation in air, with an estimated lifetime exceeding 100,000 hours.
Polymer solar cells use flexible plastic materials that absorb light and convert it to electricity. They offer better mechanical properties and thermal stability compared to other organic solar cells. This makes them promising for flexible and large-area applications.
READ ALSO: https://modernmechanics24.com/post/fermi-america-project-matador-texas/
The main challenge has been polymer chain entanglement. Polymer chains are long and tend to tangle into disordered clumps. This creates defects, reduces efficiency, and causes faster degradation during operation.
Corresponding author Wei Li explained that the team added a small amount of linearly packed small-molecule acceptor into the polymer matrix. This helped disentangle the polymer chains and transform disordered packing into ordered stacking. The approach created efficient pathways for charge transport while reducing empty space in the light-absorbing layer.
Co-author Tao Wang noted that the simple strategy simultaneously improves efficiency and stability. The device achieved an open-circuit voltage of 0.941 V, a short-circuit current density of 26.3 mA/cm², and a fill factor of 77.3% under standard testing conditions.
The solar cell uses polymeric acceptors instead of small-molecule acceptors. Polymeric macromolecular acceptors have long conjugated backbone chains that reduce free volume and limit molecular movement. This gives them superior thermal and morphological stability compared to small-molecule systems.
WATCH ALSO: https://modernmechanics24.com/post/boston-dynamics-atlas-balance-agility/
The technology still faces limits. Polymer solar cells typically show lower efficiency than other types like perovskite or silicon cells. The 19.1% result is for a lab-scale device, not yet a commercial product.
This breakthrough matters because it moves flexible organic solar cells closer to real-world use. The combination of high efficiency and exceptional stability addresses a key barrier to commercialization. The researchers stated that their work provides a practical pathway toward commercial flexible organic photovoltaics.
