Zero-dimensional (0D) all-inorganic cesium lead halide perovskites, particularly Cs4PbBr6, have been attracting wide attention due to their excellent optical properties and stability. The research also focuses on the origin of green emission from Cs4PbBr6, which has a bandgap located in the ultraviolet B (UVB) region. So far, both Cs4PbBr6 without visible emission and with green emission have been successfully prepared; however, the origin of green emission remains controversial. Photocurrent response is one of the effective approaches to explore how the photo-excited carriers influence the photo-physical properties of materials. In our study, Cs4PbBr6 particles without visible emission and with green emission were synthesized and their photocurrent response was investigated. The former showed a positive photocurrent response, while the latter showed a negative photocurrent response. The negative response was believed to be due to a built-in electric field constructed by the charged excitons in green-emissive Cs4PbBr6. From our calculations, numerous vacancies of Br are easier to appear in green-emissive Cs4PbBr6 lattices, which could combine the neutral excitons to form charged excitons. This work may contribute to the explanation of the origin of green emission of Cs4PbBr6 to some extent.
REFERENCES
1.
M. V.
Kovalenko
, L.
Protesescu
, and M. I.
Bodnarchuk
, “Properties and potential optoelectronic applications of lead halide perovskite nanocrystals
,” Science
358
(6364
), 745
–750
(2017
).2.
Q. A.
Akkerman
, G.
Rainò
, M. V.
Kovalenko
et al, “Genesis, challenges and opportunities for colloidal lead halide perovskite nanocrystals
,” Nat. Mater.
17
(5
), 394
–405
(2018
).3.
Y.
Li
, X.
Zhang
, H.
Huang
et al, “Advances in metal halide perovskite nanocrystals: Synthetic strategies, growth mechanisms, and optoelectronic applications
,” Mater. Today
32
, 204
–221
(2020
).4.
S.
Yakunin
, M.
Sytnyk
, D.
Kriegner
et al, “Detection of X-ray photons by solution-processed lead halide perovskites
,” Nat. Photonics
9
(7
), 444
–449
(2015
).5.
G.
Li
, F. W. R.
Rivarola
, N. J. L. K.
Davis
et al, “Highly efficient perovskite nanocrystal light-emitting diodes enabled by a universal crosslinking method
,” Adv. Mater.
28
(18
), 3528
–3534
(2016
).6.
X.
Li
, D.
Bi
, C.
Yi
et al, “A vacuum flash-assisted solution process for high-efficiency large-area perovskite solar cells
,” Science
353
(6294
), 58
–62
(2016
).7.
N. K.
Kumawat
, X.-K.
Liu
, D.
Kabra
et al, “Blue perovskite light-emitting diodes: Progress, challenges and future directions
,” Nanoscale
11
(5
), 2109
–2120
(2019
).8.
J.
Choi
, S.
Park
, J.
Lee
et al, “Organolead halide perovskites for low operating voltage multilevel resistive switching
,” Adv. Mater.
28
(31
), 6562
–6567
(2016
).9.
M.
Kulbak
, S.
Gupta
, N.
Kedem
et al, “Cesium enhances long-term stability of lead bromide perovskite-based solar cells
,” J. Phys. Chem. Lett.
7
(1
), 167
–172
(2016
).10.
J. S.
Manser
, J. A.
Christians
, and P. V.
Kamat
, “Intriguing optoelectronic properties of metal halide perovskites
,” Chem. Rev.
116
(21
), 12956
–13008
(2016
).11.
J. L.
Duan
, Y. Y.
Zhao
, B. L.
He
et al, “High-purity inorganic perovskite films for solar cells with 9.72% efficiency
,” Angew. Chem., Int. Ed.
57
(14
), 3787
–3791
(2018
).12.
H.
Lin
, C.
Zhou
, Y.
Tian
et al, “Low-dimensional organometal halide perovskites
,” ACS Energy Lett.
3
(1
), 54
–62
(2018
).13.
C.
Zhou
, H.
Lin
, Y.
Tian
et al, “Luminescent zero-dimensional organic metal halide hybrids with near-unity quantum efficiency
,” Chem. Sci.
9
(3
), 586
–593
(2018
).14.
D.
Han
, H.
Shi
, W.
Ming
et al, “Unraveling luminescence mechanisms in zero-dimensional halide perovskites
,” J. Mater. Chem. C
6
(24
), 6398
–6405
(2018
).15.
S.
Seth
and A.
Samanta
, “Photoluminescence of zero-dimensional perovskites and perovskite-related materials
,” J. Phys. Chem. Lett.
9
(1
), 176
–183
(2018
).16.
J.
Yin
, H.
Yang
, K.
Song
et al, “Point defects and green emission in zero-dimensional perovskites
,” J. Phys. Chem. Lett.
9
(18
), 5490
–5495
(2018
).17.
Q. A.
Akkerman
, A. L.
Abdelhady
, and L.
Manna
, “Zero-dimensional cesium lead halides: History, properties, and challenges
,” J. Phys. Chem. Lett.
9
(9
), 2326
–2337
(2018
).18.
M. I.
Saidaminov
, J.
Almutlaq
, S.
Sarmah
et al, “Pure Cs4PbBr6: Highly luminescent zero dimensional perovskite solids
,” ACS Energy Lett.
1
(4
), 840
–845
(2016
).19.
M.
De Bastiani
, I.
Dursun
, Y.
Zhang
et al, “Inside perovskites: Quantum luminescence from bulk Cs4PbBr6 single crystals
,” Chem. Mater.
29
(17
), 7108
–7113
(2017
).20.
J.
Yin
, Y.
Zhang
, A.
Bruno
et al, “Intrinsic lead ion emissions in zero-dimensional Cs4PbBr6 nanocrystals
,” ACS Energy Lett.
2
(12
), 2805
–2811
(2017
).21.
J.-H.
Cha
, J. H.
Han
, W.
Yin
et al, “Photoresponse of CsPbBr3 and Cs4PbBr6 perovskite single crystals
,” J. Phys. Chem. Lett.
8
(3
), 565
–570
(2017
).22.
D.
Chen
, Z.
Wan
, X.
Chen
et al, “Large-scale room-temperature synthesis and optical properties of perovskite-related Cs4PbBr6 fluorophores
,” J. Mater. Chem. C
4
(45
), 10646
–10653
(2016
).23.
Z.
Bao
, H.-C.
Wang
, Z.-F.
Jiang
et al, “Continuous synthesis of highly stable Cs4PbBr6 perovskite microcrystals by a microfluidic system and their application in white-light-emitting diodes
,” Inorg. Chem.
57
(21
), 13071
–13074
(2018
).24.
S.
Seth
and A.
Samanta
, “Fluorescent phase-pure zero-dimensional perovskite-related Cs4PbBr6 microdisks: Synthesis and single-particle imaging study
,” J. Phys. Chem. Lett.
8
(18
), 4461
–4467
(2017
).25.
X.
Chen
, D.
Chen
, J.
Li
et al, “Tunable CsPbBr3/Cs4PbBr6 phase transformation and their optical spectroscopic properties
,” Dalton Trans.
47
(16
), 5670
–5678
(2018
).26.
Y.
Yuan
, Q.
Yao
, J.
Zhang
et al, “Negative photoconductivity in Cs4PbBr6 single crystal
,” Phys. Chem. Chem. Phys.
22
(25
), 14276
–14283
(2020
).27.
P.
Uthirakumar
, J.-H.
Yun
, M.
Devendiran
et al, “Synthesis of thermally stable and highly luminescent spherical shaped ligand-free Cs4PbBr6 nanospheres with a single polar solvent
,” J. Lumin.
209
, 163
–169
(2019
).28.
Q. A.
Akkerman
, S.
Park
, E.
Radicchi
et al, “Nearly monodisperse insulator Cs4PbX6 (X = Cl, Br, I) nanocrystals, their mixed halide compositions, and their transformation into CsPbX3 nanocrystals
,” Nano Lett.
17
(3
), 1924
–1930
(2017
).29.
Y.
Zhang
, L.
Sinatra
, E.
Alarousu
et al, “Ligand-free nanocrystals of highly emissive Cs4PbBr6 perovskite
,” J. Phys. Chem. C
122
(11
), 6493
–6498
(2018
).30.
L.
Yang
, D.
Li
, C.
Wang
et al, “Room-temperature synthesis of pure perovskite-related Cs4PbBr6 nanocrystals and their ligand-mediated evolution into highly luminescent CsPbBr3 nanosheets
,” J. Nanopart. Res.
19
(7
), 258
–271
(2017
).31.
Y.
Zhang
, M. I.
Saidaminov
, I.
Dursun
et al, “Zero-dimensional Cs4PbBr6 perovskite nanocrystals
,” J. Phys. Chem. Lett.
8
(5
), 961
–965
(2017
).32.
S.
Kondo
, K.
Amaya
, and T.
Saito
, “Localized optical absorption in Cs4PbBr6
,” J. Phys.: Condens. Matter
14
(8
), 2093
–2099
(2002
).33.
M.
Nikl
, E.
Mihokova
, K.
Nitsch
et al, “Photoluminescence of Cs4PbBr6 crystals and thin films
,” Chem. Phys. Lett.
306
(5–6
), 280
–284
(1999
).34.
J.
Zhang
, A.
Wang
, L.
Kong
et al, “Controlled synthesis of zero-dimensional phase-pure Cs4PbBr6 perovskites crystals with high photoluminescence quantum yield
,” J. Alloys Compd.
797
, 1151
–1156
(2019
).© 2022 Author(s). Published under an exclusive license by AIP Publishing.
2022
Author(s)
You do not currently have access to this content.