A research team led by Prof. Chenkai Sun at Zhengzhou University has developed a groundbreaking low-cost polymer material for organic solar cells (OSCs), achieving unprecedented efficiency and cost-effectiveness. The study, published in SCIENCE CHINA Chemistry, introduces two polymers, PTQ14 and PTQ15, which incorporate a trifluoromethyl (CF₃) group to enhance performance while drastically reducing production costs.
Key Innovations:
- Ultralow Cost: PTQ15 costs just 35,528 $ kg-1 — only 1/5 to 1/6 of other “star” high−performance polymers like PM6 (205,725 $ kg-1) and D18 (211,432 $ kg-1). This was achieved through simplified synthesis (3-4 steps) and high yields (>80%).
- Record Efficiency: OSCs using PTQ15 with acceptors K1/K6 reached 19.96% power conversion efficiency, the highest for low-cost organic materials. The devices also showed ultrafast charge transfer (1.40 picoseconds) and minimal non-radiative energy loss (0.190 eV).
- Industrial Viability: The devices achieved 19.37% efficiency when processed in open-air (25% RH), a critical milestone for scalable manufacturing. Their estimated minimum sustainable price (0.36 $ per watt) is the lowest reported for organic photovoltaics.
Why It Matters:
Most high-efficiency OSCs rely on expensive, complex materials, hindering commercialization. PTQ15’s combination of low cost, high-efficiency, high stability, and air-process compatibility could accelerate the shift from lab to market. The team aims to push efficiency beyond 20% by optimizing donors, matching acceptors, and modulating film morphology.
About the Team:
The research was conducted at College of Chemistry, Zhengzhou University with collaborators from the Institute of Chemistry, Chinese Academy of Sciences, and Wuhan University. The work was supported by National Natural Science Foundation of China and Natural Science Foundation of Henan Province.