Two-dimensional halide perovskites featuring semiconducting organic building blocks

et al. 2021

Angewandte Chemie

Lead halide perovskites always emerge complex interactions among different elemental ions,w hichl ead to multiple intrinsic imperfections.E lemental defects,s uch as amine,P b, and Iv acancies at A-, B-, and X-sites,a re main issues to deteriorate perovskite solar cells (PSCs). Unfortunately,m ost previous passivators can only temporarily fix partial inactive vacancies as sacrificial agents.H erein, we propose ar ecovery agent, ferrocene (Fc), which can form aone-dimensional perovskite with adequate steric cavities and suitable dissociation energy to recover all elemental defects backt oa ctive light-harvesting perovskites,a nd regenerate Fc itself meanwhile.Based on this perpetual chain-reaction cycle, corresponding PSCs maintain > 10 000-hour lifetime in inert condition and > 1000-hour durabilities under various extreme environments,i ncluding continuous 85 8 8Ch eating, 50 %r elative humidity wetting,and 1-sun light soaking.

Section: Introductionmentioning

confidence: 99%

Ferrocene‐Induced Perpetual Recovery on All Elemental Defects in Perovskite Solar Cells

Chang

et al. 2021

Angewandte Chemie

“…2D halide perovskites can be considered as slabs cut from their 3D parent structures 2 . Generally, 2D perovskites arranged in the Ruddlesden‐Popper phase (or RP phase) is the most commonly observed layered structure in halide‐based perovskites 24 . The RP phase takes the general chemical formula of L 2 A n‐1 B n X 3n + 1 , in which L is a large organic cation (large‐size or long‐chain organic cations like phenylethylammonium, PEA + or butylammonium, BA + ).…”

Section: Introductionmentioning

confidence: 99%

Two‐dimensional halide perovskite quantum‐well emitters: A critical review

Park

Akriti

et al. 2021

EcoMat

Self Cite

Two‐dimensional (2D) halide perovskites can be regarded as natural organic‐inorganic hybrid quantum wells, which exhibit very promising light‐emitting applications due to their high photoluminescence quantum yield, narrow emission bandwidth, and large exciton binding energy. However, it remains a grand challenge to achieve reliable devices for both light‐emitting diodes (LEDs) and lasers utilizing phase‐pure 2D perovskites. Recently, exciting progresses have been made with respect to molecular design, optoelectronic property, and device fabrication for novel 2D perovskite hybrid quantum‐wells. In this article, we critically review the key challenges of exciton losses, charge injections, and triplet issues associated with the light‐emitting applications of such phase‐pure 2D perovskites after examining their recent breakthroughs in LEDs and lasers. Lastly, we provide a new perspective on molecular engineering strategies to address the above‐mentioned fundamental issues, which may open up a new avenue to the development of highly efficient quantum‐well emitters for solid‐state lighting and display.

“…[48,51,52] The preparation methods of light-emitting perovskite materials have been well summarized in previous review articles. [15,20,53,54] Their optical properties, as well as the structure-property relationship, have also been intensively discussed by Xing et al [55] In comparison, the polarization feature of optical properties in perovskites is relatively less mentioned, [56] although it is quite unique and potentially useful in many aspects of perovskite optoelectronics. The research on polarization properties combines studies from physicists, chemists, and material scientists, and a universal roadmap is needed to promote the future development of this research area.…”

Section: Introductionmentioning

confidence: 99%

Polarized Photoluminescence from Lead Halide Perovskites

Advanced Optical Materials

Yang

Zhang

2021

Solution‐processable lead halide perovskites possess excellent optical and electronic properties as one of the best candidates for optoelectronics. Especially, some of the perovskites show high quantum efficiency in photoluminescence, which enables their promising application in next‐generation light‐emitting materials and devices. More interestingly, the highly crystalline nature of perovskites as well as the intrinsic spin selectivity of exciton transitions introduces fascinating polarization properties into the light emission from lead halide perovskites. Herein are summarized the recent advances in the studies of polarized photoluminescence from lead halide perovskites in terms of both in‐depth understanding and potential application. The bright excitons in perovskite materials provide spin sublevels that give rise to radiative transitions carrying angular momentum, which is essential for the observation of polarized light emission. The polarization in photoluminescence can be amplified or modulated by introducing functional units such as chiral ligands in the chemical components of perovskites. Incorporating highly ordered microstructures into the perovskite materials is proved to be an effective way to further enhance the polarization properties at the macroscopic scale. The chemical and structural versatility of lead halide perovskites allows utililization of their characteristics of optical polarization in the construction of light sources, photodetectors, display devices, and so on.