Quasi-two-dimensional(2D)Ruddlesden‒Popper(RP)halide perovskites,as a kind of emerged two-dimensional layered materials,have recently achieved great attentions in lasing materials field owing to their large exciton bi...Quasi-two-dimensional(2D)Ruddlesden‒Popper(RP)halide perovskites,as a kind of emerged two-dimensional layered materials,have recently achieved great attentions in lasing materials field owing to their large exciton binding energy,high emission yield,large optical gain,and wide-range tuning of optical bandgap.This review will introduce research progresses of RP halide perovskites for lasing applications in aspects of materials,photophysics,and devices with emphasis on emission and lasing properties tailored by the molecular composition and interface.The materials,structures and fabrications are introduced in the first part.Next,the optical transitions and amplified spontaneous emission properties are discussed from the aspects of electronic structure,exciton,gain dynamics,and interface tailoring.Then,the research progresses on lasing devices are summarized and several types of lasers including VCSEL,DFB lasers,microlasers,random lasers,plasmonic lasers,and polariton lasers are discussed.At last,the challenges and perspectives would be provided.展开更多
Perovskite light-emitting diodes(PeLEDs)are considered as promising candidates for nextgeneration solution-processed full-color displays.However,the external quantum efficiencies(EQEs)and operational stabilities of de...Perovskite light-emitting diodes(PeLEDs)are considered as promising candidates for nextgeneration solution-processed full-color displays.However,the external quantum efficiencies(EQEs)and operational stabilities of deep-blue(<460 nm)PeLEDs still lag far behind their red and green counterparts.Herein,a rapid crystallization method based on hot-antisolvent bathing is proposed for realization of deep-blue PeLEDs.By promoting immediate removal of the precursor solvent from the wet perovskite films,development of the quasi-two-dimensional(2D)Ruddlesden–Popper perovskite(2D-RPP)crystals with n values>3 is hampered completely,so that phase-pure 2D-RPP films with bandgaps suitable for deep-blue PeLEDs can be obtained successfully.The uniquely developed rapid crystallization method also enables formation of randomly oriented 2D-RPP crystals,thereby improving the transfer and transport kinetics of the charge carriers.Thus,high-performance deep-blue PeLEDs emitting at 437 nm with a peak EQE of 0.63%are successfully demonstrated.The color coordinates are confirmed to be(0.165,0.044),which match well with the Rec.2020 standard blue gamut and have excellent spectral stability.展开更多
With only a few deep-level defect states having a high formation energy and dominance of shallow carrier non-trapping defects,the defect-tolerant electronic and optical properties of lead halide perovskites have made ...With only a few deep-level defect states having a high formation energy and dominance of shallow carrier non-trapping defects,the defect-tolerant electronic and optical properties of lead halide perovskites have made them appealing materials for high-efficiency,low-cost,solar cells and light-emitting devices.As such,recent observations of apparently deep-level and highly luminescent states in low-dimensional perovskites have attracted enormous attention as well as intensive debates.The observed green emission in 2D CsPb2Br5 and 0 D Cs4PbBr6 poses an enigma over whether it is originated from intrinsic point defects or simply from highly luminescent CsPbBr3 nanocrystals embedded in the otherwise transparent wide band gap semiconductors.The nature of deep-level edge emission in 2D Ruddlesden–Popper perovskites is also not well understood.In this mini review,the experimental evidences that support the opposing interpretations are analyzed,and challenges and root causes forthe controversy are discussed.Shortcomings in the current density functional theory approaches to modeling of properties and intrinsic point defects in lead halide perovskites are also noted.Selected experimental approaches are suggested to better correlate property with structure of a material and help resolve the controversies.Understanding and identification of the origin of luminescent centers will help design and engineer perovskites for wide device applications.展开更多
基金Q.Z.acknowledges the funding support from the National Natural Science Foundation of China(Nos.52072006 and 51991344)the Natural Science Foundation of Beijing Municipality(No.JQ21004)+3 种基金F.L.acknowledges the funding support from the Hubei Province Science and Technology Major Project(No.2022AAA008)the National Natural Science Foundation of China(No.12374319)the Knowledge Innovation Program of Wuhan-Basic Research(No.2022010801010349)S.C.acknowledges the funding support from the Macao Science and Technology Development Fund(Nos.FDCT-0096/2020/A2 and FDCT-0082/2022/A2).
文摘Quasi-two-dimensional(2D)Ruddlesden‒Popper(RP)halide perovskites,as a kind of emerged two-dimensional layered materials,have recently achieved great attentions in lasing materials field owing to their large exciton binding energy,high emission yield,large optical gain,and wide-range tuning of optical bandgap.This review will introduce research progresses of RP halide perovskites for lasing applications in aspects of materials,photophysics,and devices with emphasis on emission and lasing properties tailored by the molecular composition and interface.The materials,structures and fabrications are introduced in the first part.Next,the optical transitions and amplified spontaneous emission properties are discussed from the aspects of electronic structure,exciton,gain dynamics,and interface tailoring.Then,the research progresses on lasing devices are summarized and several types of lasers including VCSEL,DFB lasers,microlasers,random lasers,plasmonic lasers,and polariton lasers are discussed.At last,the challenges and perspectives would be provided.
基金National R&D Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Science and ICT(Grant Nos.2018M3D1A1058793 and 2021R1A3B1068920)the Yonsei Signature Research Cluster Program of 2021(Grant No.2021-22-0002).
文摘Perovskite light-emitting diodes(PeLEDs)are considered as promising candidates for nextgeneration solution-processed full-color displays.However,the external quantum efficiencies(EQEs)and operational stabilities of deep-blue(<460 nm)PeLEDs still lag far behind their red and green counterparts.Herein,a rapid crystallization method based on hot-antisolvent bathing is proposed for realization of deep-blue PeLEDs.By promoting immediate removal of the precursor solvent from the wet perovskite films,development of the quasi-two-dimensional(2D)Ruddlesden–Popper perovskite(2D-RPP)crystals with n values>3 is hampered completely,so that phase-pure 2D-RPP films with bandgaps suitable for deep-blue PeLEDs can be obtained successfully.The uniquely developed rapid crystallization method also enables formation of randomly oriented 2D-RPP crystals,thereby improving the transfer and transport kinetics of the charge carriers.Thus,high-performance deep-blue PeLEDs emitting at 437 nm with a peak EQE of 0.63%are successfully demonstrated.The color coordinates are confirmed to be(0.165,0.044),which match well with the Rec.2020 standard blue gamut and have excellent spectral stability.
基金support from the Robert A.Welch Foundation(E-1728)National Science Foundation(EEC-1530753)supported by the State of Texas through the Texas Center for superconductivity at the University of Houston
文摘With only a few deep-level defect states having a high formation energy and dominance of shallow carrier non-trapping defects,the defect-tolerant electronic and optical properties of lead halide perovskites have made them appealing materials for high-efficiency,low-cost,solar cells and light-emitting devices.As such,recent observations of apparently deep-level and highly luminescent states in low-dimensional perovskites have attracted enormous attention as well as intensive debates.The observed green emission in 2D CsPb2Br5 and 0 D Cs4PbBr6 poses an enigma over whether it is originated from intrinsic point defects or simply from highly luminescent CsPbBr3 nanocrystals embedded in the otherwise transparent wide band gap semiconductors.The nature of deep-level edge emission in 2D Ruddlesden–Popper perovskites is also not well understood.In this mini review,the experimental evidences that support the opposing interpretations are analyzed,and challenges and root causes forthe controversy are discussed.Shortcomings in the current density functional theory approaches to modeling of properties and intrinsic point defects in lead halide perovskites are also noted.Selected experimental approaches are suggested to better correlate property with structure of a material and help resolve the controversies.Understanding and identification of the origin of luminescent centers will help design and engineer perovskites for wide device applications.
