Formation of DY center as n-type limiting defects in octahedral semiconductors: the case of Bi-doped hybrid halide perovskites

Jin-Ling Li; Jingxiu Yang; Tom Wu; Su-Huai Wei

doi:10.1039/c8tc06222f

Formation of DY center as n-type limiting defects in octahedral semiconductors: the case of Bi-doped hybrid halide perovskites

Journal of Materials Chemistry C ◽

10.1039/c8tc06222f ◽

2019 ◽

Vol 7 (14) ◽

pp. 4230-4234 ◽

Cited By ~ 15

Author(s):

Jin-Ling Li ◽

Jingxiu Yang ◽

Tom Wu ◽

Su-Huai Wei

Keyword(s):

Dx Center ◽

Halide Perovskites ◽

Tetrahedral Semiconductors

As the DX center in tetrahedral semiconductors, we show that the DY center is an n-type limiting defect in octahedral semiconductors.

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Friedel'S law breakdown and interpretation of stacking fault images in tetrahedral semiconductors

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126408 ◽

1987 ◽

Vol 45 ◽

pp. 318-319

Author(s):

Rob. W. Glaisher ◽

A.E.C. Spargo

Keyword(s):

Relative Phase ◽

Point Group ◽

Binary Compound ◽

Stacking Fault ◽

Fold Axis ◽

Atom Pair ◽

Tetrahedral Semiconductors ◽

Group Symmetries ◽

Thin Crystal ◽

Phase Differences

Images of <11> oriented crystals with diamond structure (i.e. C,Si,Ge) are dominated by white spot contrast which, depending on thickness and defocus, can correspond to either atom-pair columns or tunnel sites. Olsen and Spence have demonstrated a method for identifying the correspondence which involves the assumed structure of a stacking fault and the preservation of point-group symmetries by correctly aligned and stigmated images. For an intrinsic stacking fault, a two-fold axis lies on a row of atoms (not tunnels) and the contrast (black/white) of the atoms is that of the {111} fringe containing the two-fold axis. The breakdown of Friedel's law renders this technique unsuitable for the related, but non-centrosymmetric binary compound sphalerite materials (e.g. GaAs, InP, CdTe). Under dynamical scattering conditions, Bijvoet related reflections (e.g. (111)/(111)) rapidly acquire relative phase differences deviating markedly from thin-crystal (kinematic) values, which alter the apparent location of the symmetry elements needed to identify the defect.

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THERMAL TRANSPORT BEHAVIORS IN LEAD HALIDE PEROVSKITES

10.1615/ihtc16.nmt.023055 ◽

2018 ◽

Author(s):

Wee-Liat Ong ◽

Giselle Elbaz ◽

Evan A. Doud ◽

Philip Kim ◽

Daniel Paley ◽

...

Keyword(s):

Thermal Transport ◽

Halide Perovskites ◽

Lead Halide

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Lead-Free Metal Halide Perovskite Nanocrystals for Photocatalysis in Water

10.26434/chemrxiv.9794270 ◽

2019 ◽

Author(s):

Subhajit Bhattacharjee ◽

Sonu Pratap Chaudhary ◽

Sayan Bhattacharyya

Keyword(s):

Charge Carrier ◽

Wide Spectrum ◽

Real Life ◽

Metal Halide ◽

Lead Free ◽

Water Medium ◽

Type I ◽

Type Ii ◽

Perovskite Layer ◽

Halide Perovskites

Metal halide perovskites with high absorption coefficient, direct generation of free charge carriers, excellent ambipolar charge carrier transport properties, point-defect tolerance, compositional versatility and solution processability are potentially transforming the photovoltaics and optoelectronics industries. However their limited ambient stability, particularly those of iodide perovskites, obscures their use as photocatalysts especially in aqueous medium. In an unprecedented approach we have exploited the photo-absorption property of the less toxic lead-free Cs3Bi2X9 (X = Br, I) nanocrystals (NCs) to catalyse the degradation of water pollutant organic dye, methylene blue (MB) in presence of visible light at room temperature. After providing a proof-of-concept with bromide perovskites in isopropanol, the perovskites are employed as photocatalysts in water medium by designing perovskite/Ag2S and perovskite/TiO2 composite systems, with Type I (or quasi Type II) and Type II alignments, respectively. Ag2S and TiO2 coatings decelerate penetration of water into the perovskite layer while facilitating charge carrier extraction. With a minimal NC loading, Cs3Bi2I9/Ag2S degrades ~90% MB within an hour. Our approach has the potential to unravel the photocatalytic properties of metal halide perovskites for a wide spectrum of real-life applications.

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