Lead selenide(PbSe)colloidal quantum dots(CQDs)are suitable for the development of the next-generation of photovoltaics(PVs)because of efcient multiple-exciton generation and strong charge coupling ability.To date,the...Lead selenide(PbSe)colloidal quantum dots(CQDs)are suitable for the development of the next-generation of photovoltaics(PVs)because of efcient multiple-exciton generation and strong charge coupling ability.To date,the reported high-efcient PbSe CQD PVs use spin-coated zinc oxide(ZnO)as the electron transport layer(ETL).However,it is found that the surface defects of ZnO present a difculty in completion of passivation,and this impedes the continuous progress of devices.To address this disadvantage,fuoride(F)anions are employed for the surface passivation of ZnO through a chemical bath deposition method(CBD).The F-passivated ZnO ETL possesses decreased densities of oxygen vacancy and a favorable band alignment.Benefting from these improvements,PbSe CQD PVs report an efciency of 10.04%,comparatively 9.4%higher than that of devices using sol-gel(SG)ZnO as ETL.We are optimistic that this interface passivation strategy has great potential in the development of solution-processed CQD optoelectronic devices.展开更多
基金the National Natural Science Foundation of China(Grant No.62105110)the Wuhan Institute of Technology(No.19QD09)the Analytical and Testing Center of HUST and the facility support of the Center for Nanoscale Characterization and Devices(CNCD),WNLO-HUST.
文摘Lead selenide(PbSe)colloidal quantum dots(CQDs)are suitable for the development of the next-generation of photovoltaics(PVs)because of efcient multiple-exciton generation and strong charge coupling ability.To date,the reported high-efcient PbSe CQD PVs use spin-coated zinc oxide(ZnO)as the electron transport layer(ETL).However,it is found that the surface defects of ZnO present a difculty in completion of passivation,and this impedes the continuous progress of devices.To address this disadvantage,fuoride(F)anions are employed for the surface passivation of ZnO through a chemical bath deposition method(CBD).The F-passivated ZnO ETL possesses decreased densities of oxygen vacancy and a favorable band alignment.Benefting from these improvements,PbSe CQD PVs report an efciency of 10.04%,comparatively 9.4%higher than that of devices using sol-gel(SG)ZnO as ETL.We are optimistic that this interface passivation strategy has great potential in the development of solution-processed CQD optoelectronic devices.