Lead sulfide quantum dots(PbS QDs)are promising candidates for high-performance solar cells due to their tunable bandgaps and low-cost solution processing.However,low carrier mobility and numerous surface defects rest...Lead sulfide quantum dots(PbS QDs)are promising candidates for high-performance solar cells due to their tunable bandgaps and low-cost solution processing.However,low carrier mobility and numerous surface defects restrict the performance of the fabricated solar cells.Herein,we report the synthesis of novel PbS-perovskite core-shell QDs to solve the low carrier mobility problem of PbS QDs via a facile hot injection method.CsPbI_(2)Br shell enabled strain-free epitaxial growth on the surface of PbS QDs because of 98%lattice match.Our results demonstrate a significant improvement in the photoluminescence and stability of the synthesized PbS-CsPbI_(2)Br QDs upon shell formation,attributed to the effective suppression of surface defects by the epitaxial shell of CsPbI_(2)Br.As a result,the obtained solar cell based on PbS-CsPbI_(2)Br core-shell QD exhibits a power conversion efficiency(PCE)of 8.43%,two times higher than that of pristine PbS QDs.Overall,the construction of PbS-CsPbI_(2)Br core-shell structures represent a promising strategy for advancing the performance of PbS QDs-based optoelectronic devices.展开更多
基金support from the National Natural Science Foundation of China(Nos.22325505,52073271,and 22305236)the USTC Research Funds of the Double First-Class Initiative(No.YD2060002034)+1 种基金the Collaborative Innovation Program of Hefei Science Center,CAS(No.2022HSC-CIP018)the China Postdoctoral Science Foundation(Nos.2023M733375 and 2023T160619).
文摘Lead sulfide quantum dots(PbS QDs)are promising candidates for high-performance solar cells due to their tunable bandgaps and low-cost solution processing.However,low carrier mobility and numerous surface defects restrict the performance of the fabricated solar cells.Herein,we report the synthesis of novel PbS-perovskite core-shell QDs to solve the low carrier mobility problem of PbS QDs via a facile hot injection method.CsPbI_(2)Br shell enabled strain-free epitaxial growth on the surface of PbS QDs because of 98%lattice match.Our results demonstrate a significant improvement in the photoluminescence and stability of the synthesized PbS-CsPbI_(2)Br QDs upon shell formation,attributed to the effective suppression of surface defects by the epitaxial shell of CsPbI_(2)Br.As a result,the obtained solar cell based on PbS-CsPbI_(2)Br core-shell QD exhibits a power conversion efficiency(PCE)of 8.43%,two times higher than that of pristine PbS QDs.Overall,the construction of PbS-CsPbI_(2)Br core-shell structures represent a promising strategy for advancing the performance of PbS QDs-based optoelectronic devices.