By combining stable radical tetramethylpiperidine nitrogen oxide(TEMPO)as end groups and perylene bisimide(PBI)as the core,a small molecular cathode interlayer(CIL)(PBI-TEMPO)was synthesized.Detailed physical-chemical...By combining stable radical tetramethylpiperidine nitrogen oxide(TEMPO)as end groups and perylene bisimide(PBI)as the core,a small molecular cathode interlayer(CIL)(PBI-TEMPO)was synthesized.Detailed physical-chemical characterizations indicate that PBI-TEMPO can form smooth film,owns low unoccupied molecular orbital(LUMO)level of−3.67 eV and can reduce the work function of silver electrode.When using PBI-TEMPO as CIL in non-fullerene organic solar cells(OSCs),the PM6:BTP-4Cl based OSCs delivered high power conversion efficiencies(PCEs)up to 17.37%,higher than those using commercial PDINO CIL with PCEs of 16.95%.Further device characterizations indicate that PBI-TEMPO can facilitate more efficient exciton dissociation and reduce charge recombination,resulting in enhanced current density and fill factor.Moreover,PBI-TEMPO displays higher thermal stability than PDINO in solution.When PBI-TEMPO and PDINO solution were heated at 150℃ for 2 h and then were used as CIL in solar cells,PBI-TEMPO-based OSCs provided a PCE of 15%,while PDINO-based OSCs only showed a PCE of 10%.These results demonstrate that incorporating TEMPO into conjugated materials is a useful strategy to create new organic semiconductors for application in OSCs.展开更多
基金National Natural Science Foundation of China(Nos.92163128,52073016,52163018)the Open Project of State Key Laboratory of Organic-Inorganic Composites,China(No.oic-202201006)the Fund of the Academy of Sciences of Jiangxi Province,China(Nos.2022YJC2017,2021YSBG22034,2021YSBG22033).
文摘By combining stable radical tetramethylpiperidine nitrogen oxide(TEMPO)as end groups and perylene bisimide(PBI)as the core,a small molecular cathode interlayer(CIL)(PBI-TEMPO)was synthesized.Detailed physical-chemical characterizations indicate that PBI-TEMPO can form smooth film,owns low unoccupied molecular orbital(LUMO)level of−3.67 eV and can reduce the work function of silver electrode.When using PBI-TEMPO as CIL in non-fullerene organic solar cells(OSCs),the PM6:BTP-4Cl based OSCs delivered high power conversion efficiencies(PCEs)up to 17.37%,higher than those using commercial PDINO CIL with PCEs of 16.95%.Further device characterizations indicate that PBI-TEMPO can facilitate more efficient exciton dissociation and reduce charge recombination,resulting in enhanced current density and fill factor.Moreover,PBI-TEMPO displays higher thermal stability than PDINO in solution.When PBI-TEMPO and PDINO solution were heated at 150℃ for 2 h and then were used as CIL in solar cells,PBI-TEMPO-based OSCs provided a PCE of 15%,while PDINO-based OSCs only showed a PCE of 10%.These results demonstrate that incorporating TEMPO into conjugated materials is a useful strategy to create new organic semiconductors for application in OSCs.
