2019 AIChE Annual Meeting

(388b) Engineering of Ruddlesden-Popper Planar Faults in Cesium Lead Halide Perovskite Nanocrystals

Authors

Morrell, M. - Presenter, University of Missouri
He, X., University of Missouri
Luo, G., Washington University in St. Louis
Thind, A., Washington University in St. Louis
White, T., University of Missouri
Hachtel, J., Oak Ridge National Laboratory
Borisevich, A., Oak Ridge National Laboratory
Idrobo, J. C., Oak Ridge National Laboratory
Mishra, R., Washington University in St. Louis
Xing, Y., University of Missouri

Engineering Ruddlesden-Popper Planar Faults in Cesium
Lead Halide Perovskite Nanocrystals

 

Maria V. Morrell,1
Xiaoqing He,2 Guangfu Luo,3 Arashdeep S. Thind,4 Tommi A. White,2

Jordan A.
Hachtel,5 Albina
Y. Borisevich,6 Juan-Carlos Idrobo,5 Rohan Mishra,3,4

and Yangchuan
Xing1

 

1 Department of Chemical
Engineering, University of Missouri, Columbia, Missouri 65211, United States

2 Electron Microscopy
Core, University of Missouri, Columbia, Missouri 65211, United States

3 Department of
Mechanical Engineering and Materials Science, Washington University in St.
Louis, St. Louis, Missouri 63130, United States

4 Institute of Materials
Science & Engineering, Washington University in St. Louis, St. Louis,
Missouri 63130, United States

5 Center for Nanophase
Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831,
United States

6 Material Science and
Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831,
United States

 

Inorganic lead halide perovskite nanocrystals
(PNCs) have recently emerged as a promising material for a variety of
optoelectronic devices, including solar cells, light-emitting diodes (LED),
photodetectors, and lasers. [1] One of the key limiting factors for the device
performance is often presence of deep–level defect states in semiconductor
structure. Extensive research on atomistic structure of CsPbBr3 revealed
that most of the intrinsic point defects induce shallow transition states,
whereas deep-level defects are rare due to their high formation energy. [2]
Engineering and study of planar defects in lead halide PNCs can be a new way to
solving the problem.

 

In our recent work, we demonstrated that Ruddlesden-Popper
(RP) planar faults could be successfully formed in CsPbBr3  colloidal
nanocrystals, trigged by a post-synthetic growth. [3] We found that PNCs with
PR faults exhibit enhanced optical properties, resulting in stronger and
narrower emission, higher quantum yield, and an exceptional light emission
stability. Demonstrated properties attributed to PR faults-induced quantum
confinement were also studied by the first-principles density-functional theory
(DFT) calculations. [4]

 

In the effort of studying the impact of RP
faults on optoelectronic properties of CsPbBr3, we aim to improve the
concentration of RP in PNCs. In our most recent work we were able to produce
CsPbBr3 PNCs highly saturated with RP faults. Such an improvement
would allow to not only experimentally define the role of RPs in colloidal
PNCs, but also test them in optoelectronic devices, such as LEDs.

 

 

References:

[1]  Shamsi. J. et al., Chem.
Rev. 2019, 119, 3296–3348

[2]  Kang, J.; Wang, L.W. J. Phys.
Chem. Lett. 2017, 8, 489−493.

[3]  Morrell, M.V., et al., ACS
Appl. Nano Mater. 2018, 1, 6091-6098.

[4]  Thind, A.S. et al., Adv.
Mater. 2019, 31, 1805047.

 

 

 

Figure 1. High-resolution TEM images of fused CsPbBr3
PNCs displaying Ruddlesden-Popper planar faults (a, b); Normalized
photoliminescense (PL) intensity decay of as-synthesized and fused PNCs (c)
[3]; Atomic resolution HAADF image of a RP planar defect with an overlaid
atomic model, and quantum wells of the macroscopic electrostatic potential (MEP)
formed due to the RP planar defects (d). [3]