Achieving 20% efficiency in halogen-free organic solar cells via isomeric additive-mediated sequential processing | EurekAlert!

Shanghai Jiao Tong University Journal Center

image:

·Isomeric molecules are introduced to fine-tune the secondary nucleation process of the donor underlayer.

·Binary organic solar cell processed with non-halogen solvent shows a champion efficiency of 20.0% (certified 19.7%).

·Mechanism of the film formation processes and the sequential processing community about solvent design rules are proposed.

Credit: Yufei Wang, Chuanlin Gao, Wen Lei, Tao Yang, Zezhou Liang, Kangbo Sun, Chaoyue Zhao, Lu Chen, Liangxiang Zhu, Haoxuan Zeng, Xiaokang Sun, Bin He, Hanlin Hu, Zeguo Tang, Mingxia Qiu, Shunpu Li, Peigang Han, Guangye Zhang.

Researchers from Shenzhen Technology University and collaborative institutions, led by Professor Guangye Zhang, have achieved a major milestone in organic solar cell (OSC) technology. Their latest work, published in Nano-Micro Letters, introduces a novel additive engineering strategy that enables 20.0% power conversion efficiency (PCE) in binary OSCs processed entirely with non-halogenated solvents. This advancement not only sets a new benchmark for toluene-processed OSCs but also offers a scalable and eco-friendly approach aligned with industrialization needs.

Why This Innovation Matters

Key Innovation: Additive-Guided Secondary Nucleation Control

To address the longstanding challenge of morphology control in sequentially processed OSCs (SqP), the team introduced two isomeric additives, ODBC and PDBC, into either the donor or acceptor layers. These additives regulate the swelling and aggregation behaviors of the active materials through non-covalent interactions, allowing for precise modulation of film morphology.

Unprecedented Device Performance

Mechanistic Insights and Morphology Control

Robust Stability and Broad Applicability

Future Outlook

This study establishes a practical, scalable pathway toward high-efficiency, halogen-free OSCs by leveraging additive-induced secondary nucleation control in the SqP framework. The use of isomeric additives like ODBC offers a powerful handle for morphology tuning, enabling enhanced crystallinity, charge transport, and long-term stability. With compatibility across multiple systems and processing conditions, this strategy holds promise for industrial-scale, environmentally friendly production of organic photovoltaics.

Stay tuned for more from Professor Guangye Zhang’s team as they continue to push the frontiers of green, high-performance organic solar technologies！

Nano-Micro Letters

10.1007/s40820-025-01715-2

Experimental study

Achieving 20% Toluene-Processed Binary Organic Solar Cells via Secondary Regulation of Donor Aggregation in Sequential Processing

1-Apr-2025

Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.