Deciphering the effect of traps on electronic charge transport properties of methylammonium lead tribromide perovskite

Halide perovskites have undergone remarkable developments as highly efficient optoelectronic materials for a variety of applications. Several studies indicated the critical role of defects on the performance of perovskite devices. However, the parameters of defects and their interplay with free charge carriers remain unclear. In this study, we explored the dynamics of free holes in methylammonium lead tribromide (MAPbBr3) single crystals using the time-of-flight (ToF) current spectroscopy. By combining ToF spectroscopy and Monte Carlo simulation, three energy states were detected in the bandgap of MAPbBr3. In addition, we found the trapping and detrapping rates of free holes ranging from a few microseconds to hundreds of microseconds. Contrary to previous studies, we revealed a strong detrapping activity of traps. We showed that these traps substantially affect the transport properties of MAPbBr3, including mobility and mobility-lifetime product. Our results provide an insight on charge transport properties of perovskite semiconductors.

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Charge Transport Properties of a Partially Reduced V2O5 Xerogel Intercalated with a Polymer Electrolyte

MRS Proceedings ◽

10.1557/proc-393-131 ◽

1995 ◽

Vol 393 ◽

Author(s):

Joyce Albritton Thomas ◽

Grant M. Kloster ◽

D. Shriver ◽

C. R. Kannewurf

Keyword(s):

Charge Transport ◽

Transport Properties ◽

Polymer Electrolyte ◽

Variable Temperature ◽

Sol Gel ◽

Electronic Conductivity ◽

Charge Carriers ◽

Electronic Charge ◽

Ionic Charge ◽

Intimate Contact

ABSTRACTRecently, there has been considerable interest in advanced materials and processing techniques for practical applications. V2O5 xerogels have generated much attention because they are layered materials that undergo reversible redox intercalation with lithium. The sol-gel process has been used to intercalate V2O5 xerogels with the polymer electrolyte, oxymethylene linked poly(ethylene oxide) - lithium triflate [(a-PEO)n(LiCF3SO3)]. The resulting nanocomposite is a mixed ionic-electronic conductor in which the ionic charge carriers in the polymer electrolyte are in intimate contact with the electronic charge carriers in the V205 xerogel. Variable-temperature electronic conductivity and thermoelectric power measurements have been performed to examine the charge transport properties.

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Critical Role of Molecular Symmetry for Charge Transport Properties: A Paradigm Learned from Quinoidal Bithieno[3,4-b]thiophenes

Chemistry of Materials ◽

10.1021/acs.chemmater.7b01551 ◽

2017 ◽

Vol 29 (11) ◽

pp. 4999-5008 ◽

Cited By ~ 15

Author(s):

Longbin Ren ◽

Dafei Yuan ◽

Eliot Gann ◽

Yuan Guo ◽

Lars Thomsen ◽

...

Keyword(s):

Charge Transport ◽

Transport Properties ◽

Critical Role ◽

Molecular Symmetry

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Mechanical and Charge Transport Properties of Alkanethiol Self-Assembled Monolayers on a Au(111) Surface: The Role of Molecular Tilt

Langmuir ◽

10.1021/la703147q ◽

2008 ◽

Vol 24 (5) ◽

pp. 2219-2223 ◽

Cited By ~ 45

Author(s):

Yabing Qi ◽

Imma Ratera ◽

Jeong Y. Park ◽

Paul D. Ashby ◽

Su Ying Quek ◽

...

Keyword(s):

Charge Transport ◽

Transport Properties ◽

Self Assembled Monolayers ◽

Assembled Monolayers ◽

Self Assembled

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Role of band states and trap states in the charge transport properties of organic semiconductors (Conference Presentation)

Organic Field-Effect Transistors XV ◽

10.1117/12.2237309 ◽

2016 ◽

Author(s):

Veaceslav Coropceanu

Keyword(s):

Charge Transport ◽

Transport Properties ◽

Organic Semiconductors ◽

Trap States

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Dynamics of Strong Coupling Between Free Charge Carriers in Organometal Halide Perovskites and Aluminum Plasmonic States

Frontiers in Chemistry ◽

10.3389/fchem.2021.818459 ◽

2022 ◽

Vol 9 ◽

Author(s):

Yang Luo ◽

Hai Wang ◽

Le-Yi Zhao ◽

Yong-Lai Zhang

Keyword(s):

Strong Coupling ◽

Transient Absorption ◽

Perovskite Solar Cells ◽

Coupled System ◽

Free Carrier ◽

Charge Carriers ◽

Free Charge ◽

Free Carriers ◽

Halide Perovskites ◽

Poor Absorption

We have investigated a strong coupled system composed of a MAPbIxCl3-x perovskite film and aluminum conical nanopits array. The hybrid states formed by surface plasmons and free carriers, rather than the traditional excitons, is observed in both steady-state reflection measurements and transient absorption spectra. In particular, under near upper band resonant excitation, the bleaching signal from the band edge of uncoupled perovskite was completely separated into two distinctive bleaching signals of the hybrid system, which is clear evidence for the formation of strong coupling states between the free carrier–plasmon state. Besides this, a Rabi splitting up to 260 meV is achieved. The appearance of the lower bands can compensate for the poor absorption of the perovskite in the NIR region. Finally, we found that the lifetime of the free carrier–SP hybrid states is slightly shorter than that of uncoupled perovskite film, which can be caused by the ultrafast damping of the SPs modes. These peculiar features on the strong coupled hybrid states based on free charge carriers can open new perspectives for novel plasmonic perovskite solar cells.

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Review of the Synthetic Chemistry Involved in the Production of Core/Shell Semiconductor Nanocrystals

Australian Journal of Chemistry ◽

10.1071/ch07046 ◽

2007 ◽

Vol 60 (7) ◽

pp. 457 ◽

Cited By ~ 90

Author(s):

Joel van Embden ◽

Jacek Jasieniak ◽

Daniel E. Gómez ◽

Paul Mulvaney ◽

Michael Giersig

Keyword(s):

Semiconductor Nanocrystals ◽

Critical Role ◽

Charge Carriers ◽

Core Shell ◽

Synthetic Chemistry ◽

Shell Material ◽

Growth Processes ◽

Passivating Layer ◽

Spectral Shifts

Passivation of CdSe semiconductor nanocrystals can be achieved by overcoating the particles with a homogeneous shell of a second semiconductor. Shell layers are grown in monolayer steps to ensure homogeneous growth of the shell. The relative band edges of the two materials determine the photoreactiveity of the resultant core-shell nanocrystals. The critical role of ligands in minimizing nucleation of the shell material during the growth of the passivating layer is emphasized. The delocalization of charge carriers into the shell layers can be followed spectroscopically during the growth processes. The relative spectral shifts are directly correlated to the relative energies of the band edges.

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