Manipulating the Transition Dipole Moment of CsPbBr ₃ Perovskite Nanocrystals for Superior Optical Properties

Journal Article · Fri Mar 08 00:00:00 EST 2019 · Nano Letters

DOI:https://doi.org/10.1021/acs.nanolett.9b00122· OSTI ID:1503670

Jurow, Matthew J.  ^[1]; Morgenstern, Thomas ^[2]; Eisler, Carissa ^[3]; Kang, Jun ^[4]; Penzo, Erika ^[5]; Do, Mai ^[5]; Engelmayer, Manuel ^[2]; Osowiecki, Wojciech T.  ^[6]; Bekenstein, Yehonadav ^[3]; Tassone, Christopher ^[7]; Wang, Lin-Wang ^[4]; Alivisatos, A. Paul  ^[8]; Brütting, Wolfgang  ^[2]; Liu, Yi  ^[1]

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1. Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States; Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
2. Institute of Physics, University of Augsburg, 86135 Augsburg, Germany
3. Department of Chemistry and Materials Science and Engineering, University of California, Berkeley, California 94720, United States
4. Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
5. Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
6. Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States; Department of Chemistry and Materials Science and Engineering, University of California, Berkeley, California 94720, United States
7. SSRL Materials Science Division, SLAC National Accelerator Laboratory, 2575 Sand Hill Rd MS 69, Menlo Park, California 94025, United States
8. Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States; Department of Chemistry and Materials Science and Engineering, University of California, Berkeley, California 94720, United States; Kavli Energy NanoScience Institute, Berkeley, California 94720, United States

Colloidal cesium lead halide perovskite nanocrystals exhibit unique photophysical properties including high quantum yields, tunable emission colors, and narrow photoluminescence spectra that have marked them as promising light emitters for applications in diverse photonic devices. Randomly oriented transition dipole moments have limited the light outcoupling efficiency of all isotropic light sources, including perovskites. In this report we design and synthesize deep blue emitting, quantum confined, perovskite nanoplates and analyze their optical properties by combining angular emission measurements with back focal plane imaging and correlating the results with physical characterization. By reducing the dimensions of the nanocrystals and depositing them face down onto a substrate by spin coating, we orient the average transition dipole moment of films into the plane of the substrate and improve the emission properties for light emitting applications. We then exploit the sensitivity of the perovskite electronic transitions to the dielectric environment at the interface between the crystal and their surroundings to reduce the angle between the average transition dipole moment and the surface to only 14° and maximize potential light emission efficiency. Furthermore, this tunability of the electronic transition that governs light emission in perovskites is unique and, coupled with their excellent photophysical properties, introduces a valuable method to extend the efficiencies and applications of perovskite based photonic devices beyond those based on current materials.

• Research Organization: Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES)
• Grant/Contract Number: AC02-05CH11231
• OSTI ID: 1503670
• Journal Information: Nano Letters, Vol. 19, Issue 4; ISSN 1530-6984
• Publisher: American Chemical Society
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
2D materials
anisotropic
back focal plane imaging
lead halide perovskite
LED
transition dipole moment