摘要
The recently reported non-fullerene acceptor(NFA)Y6 has been extensively investigated for high-performance organic solar cells.However,its charge transport property and physics have not been fully studied.In this work,we acquired a deeper understanding of the charge transport in Y6 by fabricating and characterizing thin-film transistors(TFTs),and found that the electron mobility of Y6 is over 0.3-0.4 cm^(2)/(V⋅s)in top-gate bottom-contact devices,which is at least one order of magnitude higher than that of another well-known NFA ITIC.More importantly,we observed band-like transport in Y6 spin-coated films through temperature-dependent measurements on TFTs.This is particularly amazing since such transport behavior is rarely seen in polycrystalline organic semiconductor films.Further morphology characterization and discussions indicate that the band-like transport originates from the unique molecule packing motif of Y6 and the special phase of the film.As such,this work not only demonstrates the superior charge transport property of Y6,but also suggests the great potential of developing high-mobility n-type organic semiconductors,on the basis of Y6.
基金
The authors thank the National Key Research and Development Program(No.2021YFA1200700)
the National Natural Science Foundation of China(Grant Nos.62074054 and U21A20497)
the Natural Science Foundation of Hunan Province(Nos.2019GK2245 and 2020JJ1002)
Shenzhen Science and Technology Innovation Commission(No.RCYX20200714114537036)for financial support.The work was also supported by the Fundamental Research Funds for the Central Universities.