An article written by Z. Page, Y. Liu, V. Duzhko, T. Russell and T. Emrick has been published in Science magazine.
The development of more efficient and longer lasting organic solar cells has been hampered by a trade-off between their stability in air and ease of electron extraction. This barrier exists at the interface of the light absorbing layer and top metal electrode, where it effectively impedes electron flow generated in the active layer, and as such limits the total obtainable power from the device. Zak Page and Yao Liu (Emrick and Russell groups) found that the incorporation of novel functionalized fullerenes at this interface overcomes the “electrode barrier.” Once the interlayer is in place, the solar cell devices function efficiently, independent of the electrode material (e.g. aluminum, silver, copper or gold). This opens a new opportunity to use air stable metal electrodes in solar cells, while maintaining efficient electron extraction that maximizes power output. The synthetic accessibility of these fullerenes, along with their ability to modify the electronic properties of metal electrodes, makes them excellent candidates to further improve numerous types of organic electronic devices.