Benefiting from the excellent properties such as high photoluminescence quantum yield(PLQY), wide gamut range,and narrow emission linewidth, as well as low-temperature processability, metal halide perovskite quantum d...Benefiting from the excellent properties such as high photoluminescence quantum yield(PLQY), wide gamut range,and narrow emission linewidth, as well as low-temperature processability, metal halide perovskite quantum dots(QDs)have attracted wide attention from researchers. Despite tremendous progress has been made during the past several years,the commercialization of perovskite QDs-based LEDs(PeQLEDs) is still plagued by the instability. The ion migration in halide perovskites is recognized as the key factor causing the performance degradation of PeQLEDs. In this review, the elements species of ion migration, the effects of ion migration on device performance and stability, and effective strategies to hinder/mitigate ion migration in PeQLEDs are successively discussed. Finally, the forward insights on the future research are highlighted.展开更多
Using comprehensive density functional theory calculations, we systematically investigate the structure, stability, and electronic properties of five polymorphs of GeSe monolayer, and highlight the differences in thei...Using comprehensive density functional theory calculations, we systematically investigate the structure, stability, and electronic properties of five polymorphs of GeSe monolayer, and highlight the differences in their structural and electronic properties. Our calculations show that the five free-standing polymorphs of Ge Se are stable semiconductors. β-GeSe, γ-GeSe, δ-GeSe, and ε-GeSe are indirect gap semiconductors, whereas α-GeSe is a direct gap semiconductor. We calculated Raman spectra and scanning tunneling microscopy images for the five polymorphs. Our results show that the β-GeSe monolaye r is a candidate for water splitting.展开更多
Flexible photodetectors(PDs) have huge potential for application in next-generation optoelectronic devices due to their lightweight design, portability, and excellent large area compatibility. The main challenge in th...Flexible photodetectors(PDs) have huge potential for application in next-generation optoelectronic devices due to their lightweight design, portability, and excellent large area compatibility. The main challenge in the construction of flexible PDs is to maintain the optoelectronic performance during repetitive bending, folding and stretching.Herein, flexible PDs based on ZnO nanowires(NWs) and CsPbBr3 nanosheets(NSs) were constructed by an integrated low-dimensional structure strategy. Benefiting from the flexibility of unique sheet and wire structures, the PDs were able to maintain excellent operational stability under various mechanical stresses. For example, the PDs exhibited no obvious changes in optoelectronic performance after bending for 1000 times. Additionally, the PDs exhibited an integrated broadband response ranging from ultraviolet to visible region due to the combination of the intrinsic light absorption capability of ZnO and CsPbBr3. The PDs demonstrated high responsivities of 3.10 and 0.97 A W^-1 and detectivities of 5.57×10^12 and1.71×10^12 Jones under ultraviolet and visible light irradiation,respectively. The proposed construction strategy for highly flexible and performance-integrated PDs shows great potential in future smart, wearable optoelectronic devices.展开更多
基金supported by the Natural Natural Science Foundation of China (Grant Nos.61904081 and 51672132)the Natural Science Foundation of Jiangsu Province,China (Grant No.BK20190449)the Postdoctoral Research Funding Program of Jiangsu Province,China (Grant No.2020Z144)。
文摘Benefiting from the excellent properties such as high photoluminescence quantum yield(PLQY), wide gamut range,and narrow emission linewidth, as well as low-temperature processability, metal halide perovskite quantum dots(QDs)have attracted wide attention from researchers. Despite tremendous progress has been made during the past several years,the commercialization of perovskite QDs-based LEDs(PeQLEDs) is still plagued by the instability. The ion migration in halide perovskites is recognized as the key factor causing the performance degradation of PeQLEDs. In this review, the elements species of ion migration, the effects of ion migration on device performance and stability, and effective strategies to hinder/mitigate ion migration in PeQLEDs are successively discussed. Finally, the forward insights on the future research are highlighted.
基金supported by the National Basic Research Program of China (2014CB931700)the National Natural Science Foundation of China (61222403 and 21403109)+1 种基金the Natural Science Foundation of Jiangsu province (BK20140769)the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)
文摘Using comprehensive density functional theory calculations, we systematically investigate the structure, stability, and electronic properties of five polymorphs of GeSe monolayer, and highlight the differences in their structural and electronic properties. Our calculations show that the five free-standing polymorphs of Ge Se are stable semiconductors. β-GeSe, γ-GeSe, δ-GeSe, and ε-GeSe are indirect gap semiconductors, whereas α-GeSe is a direct gap semiconductor. We calculated Raman spectra and scanning tunneling microscopy images for the five polymorphs. Our results show that the β-GeSe monolaye r is a candidate for water splitting.
基金financially supported by the National Natural Science Foundation of China (51672132 and 61604074)the Natural Science Foundation of Jiangsu Province (BK20160827 and BK20180020)+3 种基金China Postdoctoral Science Foundation (2016M590455)Open foundation of Key Laboratory of Marine Materials and Related Technologies (2016K08)the Fundamental Research Funds for the Central Universities (30917011202)PAPD of Jiangsu Higher Education Institutions
文摘Flexible photodetectors(PDs) have huge potential for application in next-generation optoelectronic devices due to their lightweight design, portability, and excellent large area compatibility. The main challenge in the construction of flexible PDs is to maintain the optoelectronic performance during repetitive bending, folding and stretching.Herein, flexible PDs based on ZnO nanowires(NWs) and CsPbBr3 nanosheets(NSs) were constructed by an integrated low-dimensional structure strategy. Benefiting from the flexibility of unique sheet and wire structures, the PDs were able to maintain excellent operational stability under various mechanical stresses. For example, the PDs exhibited no obvious changes in optoelectronic performance after bending for 1000 times. Additionally, the PDs exhibited an integrated broadband response ranging from ultraviolet to visible region due to the combination of the intrinsic light absorption capability of ZnO and CsPbBr3. The PDs demonstrated high responsivities of 3.10 and 0.97 A W^-1 and detectivities of 5.57×10^12 and1.71×10^12 Jones under ultraviolet and visible light irradiation,respectively. The proposed construction strategy for highly flexible and performance-integrated PDs shows great potential in future smart, wearable optoelectronic devices.
