Interface engineering for organic solar cells: Progress toward real-world viability

Organic solar cells offer a promising low-cost route for renewable energy, yet single-component interfacial layers frequently cannot satisfy all practical demands simultaneously. Many standalone hole-transporting or electron-transporting materials suffer from low conductivity, abundant defects, poor film-forming capability or strict processing constraints, which hold back device efficiency, long-term stability and large-area printed manufacturing.

In a review article published in Advanced Nanocomposites, researchers from South China University of Technology and City University of Hong Kong examined composite nanocomposite interlayer strategies for organic solar cells.

The team placed reported composite interlayers into three categories: inorganic composite, organic composite, and organic-inorganic hybrid systems. “Mixing different functional components together enables synergistic effects,” explains corresponding author Prof Baobing Fan. “These composite designs can tune energy-level alignment, passivate harmful interface defects, improve thin-film quality, and optimise the morphology of the light-harvesting active layer.”

As a result, solar-cell devices obtain both higher power‑conversion efficiency and greatly improved operational durability. Many of these composite materials also show better compatibility with scalable printing techniques.

“Single‑component interfacial materials can hardly meet the full set of requirements for high photovoltaic efficiency, robust long-term operational stability and low-cost large-area fabrication all at once,” says Fan. “Each standalone material is shackled by inherent drawbacks that hinder practical deployment.”

Notably, composite strategies integrate the respective merits from diverse functional constituents, offset their intrinsic weaknesses, and deliver a viable pathway to translate promising lab-scale organic solar-cell technology into scalable, real-world industrial manufacturing.

“Our classification framework can help the community quickly navigate abundant interfacial material reports,” co-author Prof Alex K.-Y. Jen. “We hope this overview inspires more rational design of composite interlayers, accelerating the commercialization of printable organic solar cells.”

Contact the author: Baobing Fan, National Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou 510640, P. R. China, baobifan@scut.edu.cn

The publisher KeAi was established by Elsevier and China Science Publishing & Media Ltd to unfold quality research globally. In 2013, our focus shifted to open access publishing. We now proudly publish more than 300 world-class, open access, English language journals, spanning all scientific disciplines. Many of these are titles we publish in partnership with prestigious societies and academic institutions, such as the National Natural Science Foundation of China (NSFC).