Chinese Academy of Sciences achieves record efficiency in organic solar cells

Researchers at the Ningbo Institute of Materials Technology and Engineering (NIMTE), part of the Chinese Academy of Sciences, have developed a new technique to improve the efficiency and stability of organic solar cells. Using a molecular locking strategy involving an ultra-thin indium chloride interlayer, the team successfully stabilized the interfaces between electrodes and hole-transport layers.

This method creates a multidentate In-O-P coordination network that anchors self-assembled monolayers, preventing them from peeling apart under heat and light exposure. In small-area laboratory tests, the cells reached a power conversion efficiency (PCE) of 20.4%. When scaled up to a larger module with an aperture area of 15.6 cm², the technology achieved a record active-area PCE of 18.8%.

In terms of durability, the modules retained over 85% of their initial efficiency after 2,000 hours of continuous operation at 25 °C. Because organic solar cells use carbon-based materials rather than silicon, they offer advantages such as being lighter, more flexible, and potentially transparent, though maintaining stability during mass production has historically been a challenge.