The Institute of Chemistry has made progress in the research of high-stability n-type photovoltaic materials

Organic photovoltaics have the advantages of light weight, flexibility and large-area processing.
Benefiting from the development of molecular photovoltaic receptor materials, their energy conversion efficiency has reached 18%
.
In order to achieve commercial applications, the long-term photothermal stability of materials and devices is still facing challenges
.
Traditional DA type electron acceptor materials generally use 3-(dicyanomethylene) indigo (INCN) and its derivatives as strong electron terminal, but INCN type acceptor materials are used in light, water, oxygen, heat and alkali.
It is prone to degradation under the action, which has become a key factor restricting the stability of the device
.
? With the support of the National Natural Science Foundation of China, the Ministry of Science and Technology and the Chinese Academy of Sciences, Zhu Xiaozhang's research group, researcher at the Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, has conducted in-depth explorations in the research of n-type molecular photovoltaic materials and devices, and developed Series of high-performance photovoltaic receptor materials, and the construction of high-performance photovoltaic devices, was invited to publish a perspective article titled n-Type Molecular Photovoltaic Materials: Design Strategies and Device Applications (Perspective, J.
Am.
Chem.
Soc.
2020, 142, 11613)
.
Based on the research team’s accumulation in the design, synthesis and device application of n-type molecular photovoltaic materials, combined with important advances in this field at home and abroad, this article summarizes and reviews the typical design strategies of high-performance n-type molecular photovoltaic materials and their Application examples in various photovoltaic devices
.
? Fused ring molecular materials have excellent charge transport properties, fluorescence properties and stability, and are widely used in field-effect transistor research
.
Recently, the research team proposed a fully fused-ring molecular design strategy to develop high-stability photovoltaic receptor materials: use dithiophene to replace the benzene ring of the classic ladder-shaped n-type semiconductor IFDM center, and use green and efficient intramolecular double-hydrocarbon activation/ring Chemical reaction, a new fused nine-ring electron acceptor material, ITYM, was designed and synthesized.
Compared with traditional INCN receptors, ITYM receptors show lower molecular reforming energy and excellent chemical, photochemical and thermal stability..
Matching ITYM with a medium-bandgap polymer electron donor achieves an efficiency close to 10%
.
Since stable electron acceptor materials are the key to the commercial application of organic photovoltaic technology, fully fused-ring electron acceptor materials have opened up a new path for the realization of high-efficiency, low-cost, and stable organic photovoltaic devices
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In addition, the high thermal stability of the fully fused ring acceptor also creates new opportunities for the development of high-performance vapor-deposited organic solar cells
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Related research results were published on CCS Chemistry (CCS Chem.
DOI: 10.
31635/ccschem.
021.
202100956), and Zhu Xiaozhang is the corresponding author of the paper
.
Design and Stability Research of Fully Fused Ring n-type Molecular Photovoltaic Acceptor Materials