High-performance ambipolar charge transport materials can reduce the manufacturing cost of OFET and OPV devices,and simplify circuit design and device structure.In order to obtain ambipolar donor-acceptor(D-A)polymer,...High-performance ambipolar charge transport materials can reduce the manufacturing cost of OFET and OPV devices,and simplify circuit design and device structure.In order to obtain ambipolar donor-acceptor(D-A)polymer,many efforts have been made through different donor and acceptor combination,halogenation or heteroatom substitution.However,the influencing factor for charge transport polarity is still much complicated.Based on intra-chain super-exchange mechanism for D-A polymer,we found that the energy alignment of donor and acceptor moiety has large impact on charge transport polarity.When the HOMO-LUMO(H-L)gap of the acceptor moiety is narrow,its HOMO/LUMO energy level both lie between the HOMO and LUMO of the donor moiety(sandwich-type energy alignment),and the corresponding D-A copolymers will be more likely ambipolar transport.And thus,take a narrow H-L gap thiazoleisoindigo(TzIID)acceptor as an example,we demonstrated that a series of TzIID based copolymers combined with wide H-L gap donor moieties can reveal ambipolar transport.We further predict several high performance ambipolar D-A copolymers(TzIID-TT etc.)with balanced electron and hole transport,whose effective mass(m_(e)^(*)=0.146 and m_(h)^(*)=0.128)is one of the smallest effective masses among ambipolar materials.展开更多
基金National Key R&D Program of China(Nos.2017YFA0204700 and 2017YFA0204502)the National Natural Science Foundation of China(No.22090022)+2 种基金Beijing Municipal natural science Foundation(No.2192013)Capacity Building for Sci-Tech Innovation-Fundamental Scientific Research Funds(Nos.19530012018 and 19530011018)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB12020200).
文摘High-performance ambipolar charge transport materials can reduce the manufacturing cost of OFET and OPV devices,and simplify circuit design and device structure.In order to obtain ambipolar donor-acceptor(D-A)polymer,many efforts have been made through different donor and acceptor combination,halogenation or heteroatom substitution.However,the influencing factor for charge transport polarity is still much complicated.Based on intra-chain super-exchange mechanism for D-A polymer,we found that the energy alignment of donor and acceptor moiety has large impact on charge transport polarity.When the HOMO-LUMO(H-L)gap of the acceptor moiety is narrow,its HOMO/LUMO energy level both lie between the HOMO and LUMO of the donor moiety(sandwich-type energy alignment),and the corresponding D-A copolymers will be more likely ambipolar transport.And thus,take a narrow H-L gap thiazoleisoindigo(TzIID)acceptor as an example,we demonstrated that a series of TzIID based copolymers combined with wide H-L gap donor moieties can reveal ambipolar transport.We further predict several high performance ambipolar D-A copolymers(TzIID-TT etc.)with balanced electron and hole transport,whose effective mass(m_(e)^(*)=0.146 and m_(h)^(*)=0.128)is one of the smallest effective masses among ambipolar materials.