Efficient Energy Funneling in Quasi‐2D Perovskites: From Light Emission to Lasing. Issue 16 (28th February 2020)

• Record Type: Journal Article
• Authors: Lei, Lei; Seyitliyev, Dovletgeldi; Stuard, Samuel; Mendes, Juliana; Dong, Qi; Fu, Xiangyu; Chen, Yi‐An; He, Siliang; Yi, Xueping; Zhu, Liping; Chang, Chih‐Hao; Ade, Harald; Gundogdu, Kenan; So, Franky
• Is Part Of: Advanced materials. Volume 32:Issue 16(2020)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-02-28
• Subjects: amplified spontaneous emission -- distributed‐feedback lasers -- energy funneling -- light‐emitting diodes -- quasi‐2D perovskites; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adma.201906571
• Languages: English
• ISSNs: 0935-9648

Abstract

Abstract: Quasi‐2D Ruddlesden–Popper halide perovskites with a large exciton binding energy, self‐assembled quantum wells, and high quantum yield draw attention for optoelectronic device applications. Thin films of these quasi‐2D perovskites consist of a mixture of domains having different dimensionality, allowing energy funneling from lower‐dimensional nanosheets (high‐bandgap domains) to 3D nanocrystals (low‐bandgap domains). High‐quality quasi‐2D perovskite (PEA)2 (FA)3 Pb4 Br13 films are fabricated by solution engineering. Grazing‐incidence wide‐angle X‐ray scattering measurements are conducted to study the crystal orientation, and transient absorption spectroscopy measurements are conducted to study the charge‐carrier dynamics. These data show that highly oriented 2D crystal films have a faster energy transfer from the high‐bandgap domains to the low‐bandgap domains (<0.5 ps) compared to the randomly oriented films. High‐performance light‐emitting diodes can be realized with these highly oriented 2D films. Finally, amplified spontaneous emission with a low threshold 4.16 µJ cm −2 is achieved and distributed feedback lasers are also demonstrated. These results show that it is important to control the morphology of the quasi‐2D films to achieve efficient energy transfer, which is a critical requirement for light‐emitting devices. Abstract : Quasi‐2D Ruddlesden–Popper halide perovskite thin films with preferential crystal orientation are achieved via solvent engineering. Such highly oriented quasi‐2D films are shown to be suitable for high‐efficiency light‐emitting diodes and low‐threshold amplified spontaneous emission due to the efficient energy transfer from the high‐bandgap domains to low‐bandgap domains. A green‐emission distributed feedback laser is demonstrated.