This highlight mainly focuses on the recent meaningful research progress of single crystals(SCs)perovskite lightemitting diodes(LEDs)made by Xiao et al.[1],published in Nature Photonics.They made a breakthrough in the...This highlight mainly focuses on the recent meaningful research progress of single crystals(SCs)perovskite lightemitting diodes(LEDs)made by Xiao et al.[1],published in Nature Photonics.They made a breakthrough in the in-situ preparation of micron-thick SCs-based perovskite films on the ITO/hole-transporter layer and successfully fabricated the LEDs.展开更多
Metal halide perovskites have received considerable attention in the field of electroluminescence,and the external quantum efficiency of perovsk'c lightemitting diodes has exceeded 20%.CH3NH3PbBr3 has been intense...Metal halide perovskites have received considerable attention in the field of electroluminescence,and the external quantum efficiency of perovsk'c lightemitting diodes has exceeded 20%.CH3NH3PbBr3 has been intensely investigated as an emitting layer in perovskite light-emitting diodes.However,perovskite films comprising CH3NH3PbBr3 often exhibit low surface coverage and poor crystallinity,leading to high current leakage,severe nonradiative recombination,and limited device performance.Herein,we demonstrate a rationale for composition engineering to obtain high-quality perovskite films.We first reduce pinholes by adding excess CH3NH3B1 to the actual CH3NH3PbBr3 films,and we then add CsBr to improve the crystalline quality and to passivate nonradiative defects.As a result,the(CH3NH3)1-xCSxPbBx based perovskite light-emitting diodes exhibit significantly improved external quantum and power efficiencies of 6.97%and 25.181m/W,respectively,representing an improvement in performance dozens of times greater than that of pristine CH3NH3PbBr3-based perovskite light-emitting diodes.Our study demonstrates that composition engineering is an effective strategy for enhancing the device performance of perovskite light-emitting diodes.展开更多
Fullerene-based electron-transporting layers(ETLs)significantly influence the defect passivation and device performance of inverted perovskite solar cells(PSCs).However,theπ-cage structures of fullerenes lead to a st...Fullerene-based electron-transporting layers(ETLs)significantly influence the defect passivation and device performance of inverted perovskite solar cells(PSCs).However,theπ-cage structures of fullerenes lead to a strong tendency to self-aggregate,which affects the long-term stability of the corresponding PSCs.Experimental results revealed that[6,6]-phenyl-C61-butyric acid methyl ester(PCBM)-based ETLs exhibit a certain degree of self-aggregation that affects the stability of the device,particularly under continuous irradiation stress.To modulate the aggregation behavior,we replaced a methyl hydrogen of PCBM with a phenyl group to yield[6,6]-phenyl-C61-butyric acid benzyl ester(PCBB).As verified through X-ray crystallography,this minor structural modification results in more non-covalent intermolecular interactions,which effectively enhanced the electron-transporting ability of the PCBB-based ETL and led to an efficiency approaching 20%.Notably,the enhanced intermolecular forces of PCBB suppressed its self-aggregation,and the corresponding device showed significantly improved stability,retaining approximately 90%of its initial efficiency after 600 h under one-sun irradiation with maximum power point tracking.These findings provide a viable approach for the design of new fullerene derivatives to tune their intermolecular interactions to suppress self-aggregation within the ETL for highperformance PSCs.展开更多
文摘This highlight mainly focuses on the recent meaningful research progress of single crystals(SCs)perovskite lightemitting diodes(LEDs)made by Xiao et al.[1],published in Nature Photonics.They made a breakthrough in the in-situ preparation of micron-thick SCs-based perovskite films on the ITO/hole-transporter layer and successfully fabricated the LEDs.
基金supported by the National Natural Science Foundation of China(Grant Nos.51802102,21805101,and 51902110)Natural Science Foundation of Fujian Province(No.2019J01057)+1 种基金Promotion Program for Young and Middle-aged Teacher in Science and Technology Research of Huaqiao University(No.ZQN-PY607)Scientific Research Funds of Huaqiao University(Nos.16BS201,17BS409,and 19BS105).
文摘Metal halide perovskites have received considerable attention in the field of electroluminescence,and the external quantum efficiency of perovsk'c lightemitting diodes has exceeded 20%.CH3NH3PbBr3 has been intensely investigated as an emitting layer in perovskite light-emitting diodes.However,perovskite films comprising CH3NH3PbBr3 often exhibit low surface coverage and poor crystallinity,leading to high current leakage,severe nonradiative recombination,and limited device performance.Herein,we demonstrate a rationale for composition engineering to obtain high-quality perovskite films.We first reduce pinholes by adding excess CH3NH3B1 to the actual CH3NH3PbBr3 films,and we then add CsBr to improve the crystalline quality and to passivate nonradiative defects.As a result,the(CH3NH3)1-xCSxPbBx based perovskite light-emitting diodes exhibit significantly improved external quantum and power efficiencies of 6.97%and 25.181m/W,respectively,representing an improvement in performance dozens of times greater than that of pristine CH3NH3PbBr3-based perovskite light-emitting diodes.Our study demonstrates that composition engineering is an effective strategy for enhancing the device performance of perovskite light-emitting diodes.
基金financial supports from the National Natural Science Foundation of China(51902110,51802102 and 21805101)the Scientific Research Funds of Huaqiao University(19BS105,16BS201 and 17BS409)+1 种基金Fundamental Research Funds for the Central Universities(ZQN-806,ZQN-PY607)the US National Science Foundation for generous support of this work under CHE1801317。
文摘Fullerene-based electron-transporting layers(ETLs)significantly influence the defect passivation and device performance of inverted perovskite solar cells(PSCs).However,theπ-cage structures of fullerenes lead to a strong tendency to self-aggregate,which affects the long-term stability of the corresponding PSCs.Experimental results revealed that[6,6]-phenyl-C61-butyric acid methyl ester(PCBM)-based ETLs exhibit a certain degree of self-aggregation that affects the stability of the device,particularly under continuous irradiation stress.To modulate the aggregation behavior,we replaced a methyl hydrogen of PCBM with a phenyl group to yield[6,6]-phenyl-C61-butyric acid benzyl ester(PCBB).As verified through X-ray crystallography,this minor structural modification results in more non-covalent intermolecular interactions,which effectively enhanced the electron-transporting ability of the PCBB-based ETL and led to an efficiency approaching 20%.Notably,the enhanced intermolecular forces of PCBB suppressed its self-aggregation,and the corresponding device showed significantly improved stability,retaining approximately 90%of its initial efficiency after 600 h under one-sun irradiation with maximum power point tracking.These findings provide a viable approach for the design of new fullerene derivatives to tune their intermolecular interactions to suppress self-aggregation within the ETL for highperformance PSCs.
