Related Experiment Video
Updated: Feb 12, 2026
04:14
Facile Synthesis of Colloidal Lead Halide Perovskite Nanoplatelets via Ligand-Assisted Reprecipitation
Published on: October 1, 2019
13.6K
Layered Halide Double Perovskites: Dimensional Reduction of Cs2AgBiBr6.
Bridget A Connor1, Linn Leppert2, Matthew D Smith1
1Department of Chemistry , Stanford University , Stanford , California 94305 , United States.
Journal of the American Chemical Society
|March 27, 2018
Summary
Synthesizing 2D halide double perovskites, (BA)4AgBiBr8 and (BA)2CsAgBiBr7, reveals dimensional confinement effects. These materials exhibit unique electronic and optical properties distinct from 3D analogues, expanding halide perovskite diversity.
Area of Science:
- Materials Science
- Solid-State Chemistry
- Condensed Matter Physics
Background:
- Halide perovskites are promising optoelectronic materials.
- Three-dimensional (3D) double perovskite Cs2AgBiBr6 has been recently reported.
- Dimensional confinement effects in halide perovskites are not fully understood.
Purpose of the Study:
- To synthesize and investigate 2D analogues of Cs2AgBiBr6.
- To understand the impact of dimensional confinement on halide double perovskites.
- To explore the electronic and optical properties of these novel 2D materials.
Main Methods:
- Synthesis of two-dimensional (2D) layered perovskites: (BA)4AgBiBr8 and (BA)2CsAgBiBr7.
- Electronic structure calculations to determine bandgap properties.
- Optical characterization to analyze photophysical properties.
Main Results:
- Synthesized 2D halide double perovskites with mono- and bilayer metal-halide sheets.
- Electronic structure calculations show a transition from indirect to direct bandgap upon reducing dimensionality.
- Optical characterization reveals distinct photophysical properties compared to 3D and lead-halide analogues.
Conclusions:
- Dimensional reduction significantly alters the electronic and optical properties of halide double perovskites.
- Hybrid layered derivatives offer expanded compositional and electronic diversity.
- These findings pave the way for designing novel perovskite materials with tailored optoelectronic functionalities.
More Related Videos
Related Concept Videos
01:19Acid Halides to Alcohols: LiAlH4 Reduction
4.0K
Acid halides are reduced to alcohols in the presence of a strong reducing agent like lithium aluminum hydride.
The mechanism proceeds in three steps. First, the nucleophilic hydride ion attacks the carbonyl carbon of the acid halide to form a tetrahedral intermediate. Next, the carbonyl group is re-formed, and the halide ion departs as a leaving group, generating an aldehyde. A second nucleophilic attack by the hydride yields an alkoxide ion, which, upon protonation, gives a primary alcohol as...
The mechanism proceeds in three steps. First, the nucleophilic hydride ion attacks the carbonyl carbon of the acid halide to form a tetrahedral intermediate. Next, the carbonyl group is re-formed, and the halide ion departs as a leaving group, generating an aldehyde. A second nucleophilic attack by the hydride yields an alkoxide ion, which, upon protonation, gives a primary alcohol as...
4.0K
02:45Alkyl Halides
20.1K
Structural Properties
Alkyl halides are halogen-substituted alkanes wherein one or more hydrogen atoms of an alkane is replaced by a halogen atom such as fluorine, chlorine, bromine, or iodine. The carbon atom in an alkyl halide is bonded to the halogen atom, which is sp3-hybridized and exhibits a tetrahedral shape.
Unlike alkyl halides, compounds in which a halogen atom is bonded to an sp2 -hybridized carbon atom of a carbon-carbon double bond (C=C) are called vinyl halides. Whereas aryl...
Alkyl halides are halogen-substituted alkanes wherein one or more hydrogen atoms of an alkane is replaced by a halogen atom such as fluorine, chlorine, bromine, or iodine. The carbon atom in an alkyl halide is bonded to the halogen atom, which is sp3-hybridized and exhibits a tetrahedral shape.
Unlike alkyl halides, compounds in which a halogen atom is bonded to an sp2 -hybridized carbon atom of a carbon-carbon double bond (C=C) are called vinyl halides. Whereas aryl...
20.1K
03:11Oxidation-Reduction Reactions
75.9K
Oxidation–Reduction Reactions
75.9K
01:12Acid Halides to Esters: Alcoholysis
4.1K
Alcoholysis is a nucleophilic acyl substitution reaction in which an alcohol functions as a nucleophile. Acid halides react with alcohol to produce esters. The mechanism proceeds in three steps:
4.1K
01:22Mass Spectrometry: Alkyl Halide Fragmentation
1.6K
Chlorine isotopes exist as 35Cl and 37Cl in a 3:1 ratio, while bromine isotopes exist as 79Br and 81Br in a 1:1 ratio. The mass spectrum of alkyl halides typically produces two distinct molecular ion peaks, the molecular ion peak, [M], and the molecular ion plus two, [M + 2] peak. The relative heights of these two peaks are proportional to the isotopic abundance ratios of the halide. For example, 2‐chloropropane and 1‐bromopropane display two peaks with relative peak heights in a 3:1 and...
1.6K
01:01Acid Halides to Carboxylic Acids: Hydrolysis
3.6K
Hydrolysis of acid halides is a nucleophilic acyl substitution reaction in which acid halides react with water to give carboxylic acids. The reaction occurs readily and does not require acid or a base catalyst.
As shown below, the mechanism involves a nucleophilic attack by water at the carbonyl carbon to form a tetrahedral intermediate. This is followed by the reformation of the carbon–oxygen π bond along with the departure of a halide ion. A final proton transfer step yields carboxylic...
As shown below, the mechanism involves a nucleophilic attack by water at the carbonyl carbon to form a tetrahedral intermediate. This is followed by the reformation of the carbon–oxygen π bond along with the departure of a halide ion. A final proton transfer step yields carboxylic...
3.6K