Advanced

Microscopic morphology independence in linear absorption cross-section of CsPbBr3 nanocrystalsMicroscopic morphology independence in linear absorption cross-section of CsPbBr3 nanocrystals

Zhang, Fengying LU ; Liu, Yuchen LU ; Wei, Shiqian ; Chen, Junsheng LU ; Zhou, Ying ; He, Rongxing ; Pullerits, Tõnu LU and Zheng, Kaibo LU (2021) In SCIENCE CHINA Materials
Abstract

Multiple morphologies of colloidal perovskite nanocrystals (NCs) diversify their optical and electronic properties. Among them, the linear absorption cross-section (σ) is a primary parameter to determine their intrinsic photophysical features, and consequently, application potential. Herein, three morphologies of all-inorganic hybrid colloidal perovskite CsPbBr3 NCs, nanocubes (NBs), nanoplatelets (NLs), and nanowires (NWs), were targeted, and their linear σ values were obtained through femtosecond transient absorption (TA) spectroscopy analysis. At high excitation energy well above the bandgap, the σ per particle of all CsPbBr3 NCs linearly increased with the particle volume (VNC) regardless of the... (More)

Multiple morphologies of colloidal perovskite nanocrystals (NCs) diversify their optical and electronic properties. Among them, the linear absorption cross-section (σ) is a primary parameter to determine their intrinsic photophysical features, and consequently, application potential. Herein, three morphologies of all-inorganic hybrid colloidal perovskite CsPbBr3 NCs, nanocubes (NBs), nanoplatelets (NLs), and nanowires (NWs), were targeted, and their linear σ values were obtained through femtosecond transient absorption (TA) spectroscopy analysis. At high excitation energy well above the bandgap, the σ per particle of all CsPbBr3 NCs linearly increased with the particle volume (VNC) regardless of the morphology with the value of σ400 = 9.45 × 104 cm−1 × VNC (cm2). Density functional theory (DFT) calculation confirmed the negligible influence of shapes on the optical selection rules. The Einstein spontaneous emission coefficients calculated from the σ values define the intrinsic radiative recombination rate. However, reduced size dependence is observed when the excitation energy is close to the bandgap (i.e., at 460 nm) with the value of σ460 = 2.82 × 108 cm0.65 × (VNC)0.45 (cm2). This should be ascribed to the discrete energy levels as well as lower density of states close to the band edge for perovskite NCs. These results provide in-depth insight into the optical characteristics for perovskite NCs.

(Less)
Please use this url to cite or link to this publication:
author
; ; ; ; ; ; and
organization
publishing date
type
Contribution to journal
publication status
epub
subject
keywords
absorption cross-section, density functional theory, multiple morphologies, radiative recombination, transient absorption spectroscopy
in
SCIENCE CHINA Materials
publisher
Science in China Press
external identifiers
  • scopus:85100199299
ISSN
2095-8226
DOI
10.1007/s40843-020-1555-1
language
English
LU publication?
yes
id
10153387-0b11-48ca-9bcc-81496e815308
date added to LUP
2021-02-12 13:11:09
date last changed
2021-02-12 13:17:22
@article{10153387-0b11-48ca-9bcc-81496e815308,
  abstract     = {<p>Multiple morphologies of colloidal perovskite nanocrystals (NCs) diversify their optical and electronic properties. Among them, the linear absorption cross-section (σ) is a primary parameter to determine their intrinsic photophysical features, and consequently, application potential. Herein, three morphologies of all-inorganic hybrid colloidal perovskite CsPbBr<sub>3</sub> NCs, nanocubes (NBs), nanoplatelets (NLs), and nanowires (NWs), were targeted, and their linear σ values were obtained through femtosecond transient absorption (TA) spectroscopy analysis. At high excitation energy well above the bandgap, the σ per particle of all CsPbBr<sub>3</sub> NCs linearly increased with the particle volume (V<sub>NC</sub>) regardless of the morphology with the value of σ<sub>400</sub> = 9.45 × 10<sup>4</sup> cm<sup>−1</sup> × V<sub>NC</sub> (cm<sup>2</sup>). Density functional theory (DFT) calculation confirmed the negligible influence of shapes on the optical selection rules. The Einstein spontaneous emission coefficients calculated from the σ values define the intrinsic radiative recombination rate. However, reduced size dependence is observed when the excitation energy is close to the bandgap (i.e., at 460 nm) with the value of σ<sub>460</sub> = 2.82 × 10<sup>8</sup> cm<sup>0.65</sup> × (V<sub>NC</sub>)<sup>0.45</sup> (cm<sup>2</sup>). This should be ascribed to the discrete energy levels as well as lower density of states close to the band edge for perovskite NCs. These results provide in-depth insight into the optical characteristics for perovskite NCs.</p>},
  author       = {Zhang, Fengying and Liu, Yuchen and Wei, Shiqian and Chen, Junsheng and Zhou, Ying and He, Rongxing and Pullerits, Tõnu and Zheng, Kaibo},
  issn         = {2095-8226},
  language     = {eng},
  month        = {01},
  publisher    = {Science in China Press},
  series       = {SCIENCE CHINA Materials},
  title        = {Microscopic morphology independence in linear absorption cross-section of CsPbBr<sub>3</sub> nanocrystalsMicroscopic morphology independence in linear absorption cross-section of CsPbBr<sub>3</sub> nanocrystals},
  url          = {http://dx.doi.org/10.1007/s40843-020-1555-1},
  doi          = {10.1007/s40843-020-1555-1},
  year         = {2021},
}