Inorganic lead halide perovskites are attractive optoelectronic materials owing to their relative stability compared to organic cation alternatives.The chemical vapor deposition(CVD) method offers potential for high q...Inorganic lead halide perovskites are attractive optoelectronic materials owing to their relative stability compared to organic cation alternatives.The chemical vapor deposition(CVD) method offers potential for high quality perovskite film growth.The deposition temperature is a critical parameter determining the film quality owing to the melting difference between the precursors.Here,perovskite films were deposited by the CVD method at various temperatures between 500-800℃.The perovskite phase converts from CsPb_(2)Br_(5) to CsPbBr_(3) gradually as the deposition temperature is increased.The grain size of the perovskite films also increases with temperature.The phase transition mechanism was clarified.The photoexcited state dynamics were investigated by spatially and temporally resolved fluorescence measurements.The perovskite film deposited under 750℃ condition is of the CsPbBr_(3) phase,showing low trap-state density and large crystalline grain size.A photodetector based on perovskite films shows high photocurrent and an on/off ratio of ~2.5×10^(4).展开更多
A wide range of techniques has been developed to image biological samples at high spatial and temporal resolution.In this paper,we report recent results from deep-UV confocal fAuorescence microscopy to image inherent ...A wide range of techniques has been developed to image biological samples at high spatial and temporal resolution.In this paper,we report recent results from deep-UV confocal fAuorescence microscopy to image inherent emission from fuorophores such as tryptophan,and structured ilumination microscopy(SIM)of biological materials.One motivation for developing deep-UV fhuorescence imaging and SIM is to provide methods to complement our measurements in the emerging field of X-ray coherent diffractive imaging.展开更多
Organic optoelectronics have received tremendous attentions in the past few decades,which are benefitting from the rapid development of organic semiconductors and their unique merits such as flexible design,low-cost p...Organic optoelectronics have received tremendous attentions in the past few decades,which are benefitting from the rapid development of organic semiconductors and their unique merits such as flexible design,low-cost production,and rich optoelectronic properties.Triplet excitons with two parallel electronic spins generated in the organic optoelectronic devices have significant effects on the device performance.In this review,a timely summary and brief discussion of the management and utilization of the triplet excitons in organic optoelectronic devices are given.We firstly summarized the studies and applications of triplet excitons in optical-to-electrical and electrical-to-optical devices,including solar cells,organic light-emitting diodes(OLEDs)and organic light-emitting transistors(OLETs).Particularly,the pioneering advances of triplet management in OLETs are reviewed for the first time.Additionally,two possible strategies for breaking the theoretical limit of internal quantum efficiency(IQE)in electroluminescent devices by fully taking the advantages of triplet excitons are proposed.Finally,the challenges and perspective of existing issues in this field for further improving the performance of optoelectronic devices and other related research directions are also provided.展开更多
基金supported by the National Natural Science Foundation of China(Nos.61804015,11574181)Natural Science Foundation of Jiangsu Province(No.BK20180181)+1 种基金the Natural Science Foundation of Jiangsu Higher Education(No.17KJB140001)support from the ARC Centre of Excellence in Exciton Science(No.CE170100026)。
文摘Inorganic lead halide perovskites are attractive optoelectronic materials owing to their relative stability compared to organic cation alternatives.The chemical vapor deposition(CVD) method offers potential for high quality perovskite film growth.The deposition temperature is a critical parameter determining the film quality owing to the melting difference between the precursors.Here,perovskite films were deposited by the CVD method at various temperatures between 500-800℃.The perovskite phase converts from CsPb_(2)Br_(5) to CsPbBr_(3) gradually as the deposition temperature is increased.The grain size of the perovskite films also increases with temperature.The phase transition mechanism was clarified.The photoexcited state dynamics were investigated by spatially and temporally resolved fluorescence measurements.The perovskite film deposited under 750℃ condition is of the CsPbBr_(3) phase,showing low trap-state density and large crystalline grain size.A photodetector based on perovskite films shows high photocurrent and an on/off ratio of ~2.5×10^(4).
基金We acknowledge the support of the Australian Research Council for the Center of Excellence for Coherent X-ray Science(CE0561787).
文摘A wide range of techniques has been developed to image biological samples at high spatial and temporal resolution.In this paper,we report recent results from deep-UV confocal fAuorescence microscopy to image inherent emission from fuorophores such as tryptophan,and structured ilumination microscopy(SIM)of biological materials.One motivation for developing deep-UV fhuorescence imaging and SIM is to provide methods to complement our measurements in the emerging field of X-ray coherent diffractive imaging.
基金support from the Ministry of Science and Technology of China(2022YFB3603800,2023YFB3609000)the Natural Science Foundation of China(52233010,52103245,and 22021002)+3 种基金the CAS Project for Young Scientists in Basic Research(YSBR-053)the Beijing National Laboratory for Molecular Sciences(BNLMS-CXXM-202012)the Australian Research Council(ARC DP200103036)support from the Australian Research Council through the ARC centre of Excellence in Exciton Science(CE170100026).
文摘Organic optoelectronics have received tremendous attentions in the past few decades,which are benefitting from the rapid development of organic semiconductors and their unique merits such as flexible design,low-cost production,and rich optoelectronic properties.Triplet excitons with two parallel electronic spins generated in the organic optoelectronic devices have significant effects on the device performance.In this review,a timely summary and brief discussion of the management and utilization of the triplet excitons in organic optoelectronic devices are given.We firstly summarized the studies and applications of triplet excitons in optical-to-electrical and electrical-to-optical devices,including solar cells,organic light-emitting diodes(OLEDs)and organic light-emitting transistors(OLETs).Particularly,the pioneering advances of triplet management in OLETs are reviewed for the first time.Additionally,two possible strategies for breaking the theoretical limit of internal quantum efficiency(IQE)in electroluminescent devices by fully taking the advantages of triplet excitons are proposed.Finally,the challenges and perspective of existing issues in this field for further improving the performance of optoelectronic devices and other related research directions are also provided.
