Non-Fullerene Organic Solar Cell Technologies

Non-fullerene organic solar cells employ alternative electron acceptors to traditional fullerene derivatives, offering finely tunable optical absorption, reduced synthetic complexity and improved thermal stability. These systems typically blend donor and acceptor materials into a bulk heterojunction architecture, in which interpenetrating networks facilitate exciton dissociation and charge transport. Advances in molecular design—such as helical semiconductors, bay‐functionalised perylene diimides and three‐dimensional acceptor scaffolds—have yielded materials with red-shifted absorption, high electron mobility and reduced charge recombination. The global significance of these technologies is underscored by demonstrated power conversion efficiencies exceeding 10 %, along with improved device lifetimes and compatibility with roll-to-roll processing. Practical applications range from large-area photovoltaics to low-power indoor energy harvesting, highlighting the potential of non-fullerene systems for sustainable energy deployment.

Research from Nature Portfolio

Recent studies have revealed helical molecular semiconductors that rival fullerene derivatives in efficiency. By employing chiral backbones, these acceptors form mesh-like networks within the active layer, promoting efficient exciton separation and delivering power conversion efficiencies above 8 %. Ultrafast spectroscopy demonstrated rapid electron and hole transfer at the donor–acceptor interface, confirming the design principles for non-fullerene acceptors with tailored morphology. In parallel, comparative morphological analyses of perylene diimide and fullerene blends have pinpointed the nanostructural origin of performance disparities. Researchers identified that perylene derivatives can exhibit favourable polymer fibril formation but suffer from unbalanced charge transport and energetic disorder. Detailed scattering and microscopy studies have guided the suppression of recombination losses by controlling domain purity and polymer crystallinity, leading to notable improvements in fill factor and overall device performance.

Non-Fullerene Organic Solar Cell Technologies publication trend

The graph below shows the total number of articles in non-fullerene organic solar cell technologies across all publications each year (not limited to Nature Index journals).

Technical terms

Non-fullerene acceptor: An organic molecule that accepts electrons in a solar cell, distinct from traditional fullerene derivatives, offering tunable properties and improved stability.

Bulk heterojunction: A nano-scale interpenetrating network of donor and acceptor materials providing large interface area for exciton dissociation and pathways for charge transport.

Exciton: A bound electron–hole pair generated by photon absorption, which must reach a donor–acceptor interface to separate into free charges.

Power conversion efficiency (PCE): The ratio of electrical power output to incident light power, expressed as a percentage, and a key metric for solar cell performance.

Charge carrier mobility: The ease with which electrons or holes move through a semiconductor, influencing device current and fill factor.

References

1. Molecular helices as electron acceptors in high-performance bulk heterojunction solar cells. Nature Communications (2015).
2. Development of Perylene-Based Non-Fullerene Acceptors through Bay-Functionalization Strategy. Materials (2020).
3. A Tetraperylene Diimides Based 3D Nonfullerene Acceptor for Efficient Organic Photovoltaics. Advanced Science (2015).
4. Unraveling the efficiency-limiting morphological issues of the perylene diimide-based non-fullerene organic solar cells. Scientific Reports (2018).
5. Efficient soluble PTCBI-type non-fullerene acceptor materials for organic solar cells. Frontiers of Optoelectronics (2023).
6. Isomerization of Perylene Diimide Based Acceptors Enabling High‐Performance Nonfullerene Organic Solar Cells with Excellent Fill Factor. Advanced Science (2019).
7. N-Annulated Perylene Diimide Non-Fullerene Acceptors for Organic Photovoltaics. Colorants (2023).