A 3D Lead Iodide Hybrid Based on a 2D Perovskite Subnetwork

Lead halide perovskites have emerged as promising materials for various optoelectronic applications. For photovoltaics, the reference compound is the 3D perovskite (MA)PbI3 (MA+ = methylammonium). However, this material suffers from instabilities towards humidity or light. This makes the search of new stable 3D lead halide materials very relevant. A strategy is the use of intermediate size cations instead of MA, which are not suitable to form the 3D ABX3 perovskites or 2D perovskites. Here, we report on a novel 3D metal halide hybrid material based on the intermediate size cation hydroxypropylammonium (HPA+), (HPA)6(MA)Pb5I17. We will see that extending the carbon chain length from two CH2 units (in the hydroxylethylammonium cation, HEA+) to three (HPA+) precludes the formation of a perovskite network as found in the lead and iodide deficient perovskite (HEA,MA)1+xPbxI3−x. In (HPA)6(MA)Pb5I17 the 3D lead halide network results from a 2D perovskite subnetworks linked by a PbI6 octahedra sharing its faces. DFT calculations confirm the direct band gap and reveal the peculiar band structure of this 3D network. On one hand the valence band has a 1D nature involving the p orbitals of the halide. On the other, the conduction band possesses a clear 2D character involving hybridization between the p orbitals of the metal and the halide.

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A novel water-resistant and thermally stable black lead halide perovskite, phenyl viologen lead iodide C22H18N2(PbI3)2

Dalton Transactions ◽

10.1039/c9dt04148f ◽

2020 ◽

Vol 49 (8) ◽

pp. 2616-2627 ◽

Cited By ~ 3

Author(s):

Alessandro Latini ◽

Simone Quaranta ◽

Francesca Menchini ◽

Nicola Lisi ◽

Diego Di Girolamo ◽

...

Keyword(s):

Band Gap ◽

Thermally Stable ◽

Lead Iodide ◽

Direct Band Gap ◽

Direct Band ◽

Halide Perovskite ◽

Stable Hybrid ◽

Lead Halide

A novel black, direct band gap (Eg = 1.32 eV), water and temperature stable hybrid lead halide perovskite was synthesized and characterized.

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Stabilizing lead halide perovskites with quaternary ammonium cations: the case of tetramethylammonium lead iodide

Physical Chemistry Chemical Physics ◽

10.1039/c9cp04051j ◽

2019 ◽

Vol 21 (44) ◽

pp. 24768-24777 ◽

Cited By ~ 1

Author(s):

Andrea Ciccioli ◽

Riccardo Panetta ◽

Alessio Luongo ◽

Bruno Brunetti ◽

Stefano Vecchio Ciprioti ◽

...

Keyword(s):

Quaternary Ammonium ◽

Lead Iodide ◽

Quaternary Ammonium Cations ◽

Halide Perovskites ◽

Lead Halide

N(CH3)4PbI3 is much more stable than CH3NH3PbI3, both kinetically and thermodynamically, and much less prone to water-induced degradation; the use of quaternary ammonium cations may be effective to produce more stable lead halide perovskites.

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Microfluidic Approach for Lead Halide Perovskite Flexible Phototransistors

Electronics ◽

10.3390/electronics9111852 ◽

2020 ◽

Vol 9 (11) ◽

pp. 1852

Author(s):

Fatemeh Khorramshahi ◽

Arash Takshi

Keyword(s):

Room Temperature ◽

Lead Iodide ◽

Current Modulation ◽

Facile Fabrication ◽

Halide Perovskites ◽

P Type ◽

Methylammonium Lead Iodide ◽

Source Structure ◽

Polycrystalline Form ◽

Lead Halide

Lead halide perovskites possess outstanding optical characteristics that can be employed in the fabrication of phototransistors. However, due to low current modulation at room temperature, sensitivity to the ambient environment, lack of patterning techniques and low carrier mobility of polycrystalline form, investigation in perovskite phototransistors has been limited to rigid substrates such as silicon and glass to improve the film quality. Here, we report on room temperature current modulation in a methylammonium lead iodide perovskite (MAPbI3) flexible transistor made by an extremely cheap and facile fabrication process. The proposed phototransistor has the top-gate configuration with a lateral drain–channel–source structure. The device performed in the linear and saturation regions both in the dark and under white light in different current ranges according to the illumination conditions. The transistor showed p-type transport characteristics and the field effect mobility of the device was calculated to be ~1.7 cm2 V−1 s−1. This study is expected to contribute to the development of MAPbI3 flexible phototransistors.

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Morphological and Optical Tuning of Lead-Free Cs2SnX6 (X = I, Br) Perovskite Nanocrystals by Ligand Engineering

Frontiers in Electronics ◽

10.3389/felec.2021.703182 ◽

2021 ◽

Vol 2 ◽

Author(s):

Alessandro Veronese ◽

Carlo Ciarrocchi ◽

Marcello Marelli ◽

Paolo Quadrelli ◽

Maddalena Patrini ◽

...

Keyword(s):

Three Dimensional ◽

Blue Shift ◽

Carbon Chain ◽

Lead Free ◽

Future Research ◽

Promising Alternative ◽

Perovskite Nanocrystals ◽

Halide Perovskites ◽

Capping Ligands ◽

Lead Halide

In order to overcome the toxicity of lead halide perovskites, in recent years the research has focused on replacing lead with more environmentally friendly metals like tin, germanium, bismuth or antimony. However, lead-free perovskites still present instability issues and low performances that do not make them competitive when compared to their lead-based counterparts. Here we report the synthesis of lead-free Cs2SnX6 (X = Br, I) nanostructures of different shapes by using various surface ligands. These compounds are a promising alternative to lead halide perovskites in which the replacement of divalent lead (Pb(II)) with tetravalent tin (Sn(IV)) causes a modification of the standard perovskite structure. We investigate the effects of different amines on the morphology and size of Cs2SnX6 (X = Br, I) nanocrystals, presenting a facile hot-infection method to directly synthesize three-dimensional (3D) nanoparticles as well as two-dimensional (2D) nanoplatelets. The amines not only modify the shape of the crystals, but also affect their optical properties: increasing the length of the amine carbon chain we observe a widening in the bandgap of the compounds and a blue-shift of their emission peak. Alongside the tuning of the chemical composition and the reduction of the crystal size, our study offers a new insight in controlling the physical properties of perovskite nanocrystals by means of the capping ligands, paving the way for future research on lead-free materials.

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Electronic and optical properties of bulk and surface of CsPbBr3 inorganic halide perovskite a first principles DFT 1/2 approach

Scientific Reports ◽

10.1038/s41598-021-99551-y ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Mohammed Ezzeldien ◽

Samah Al-Qaisi ◽

Z. A. Alrowaili ◽

Meshal Alzaid ◽

E. Maskar ◽

...

Keyword(s):

Optical Properties ◽

Band Gap ◽

Visible Spectrum ◽

Ultra Violet ◽

Electronic And Optical Properties ◽

Direct Band ◽

Halide Perovskites ◽

Electro Magnetic ◽

Experimental Findings ◽

Lead Halide

AbstractThis work aims to test the effectiveness of newly developed DFT-1/2 functional in calculating the electronic and optical properties of inorganic lead halide perovskites CsPbBr3. Herein, from DFT-1/2 we have obtained the direct band gap of 2.36 eV and 3.82 eV for orthorhombic bulk and 001-surface, respectively. The calculated energy band gap is in qualitative agreement with the experimental findings. The bandgap of ultra-thin film of CsPbBr3 is found to be 3.82 eV, which is more than the expected range 1.23-3.10 eV. However, we have found that the bandgap can be reduced by increasing the surface thickness. Thus, the system under investigation looks promising for optoelectronic and photocatalysis applications, due to the bandgap matching and high optical absorption in UV–Vis (Ultra violet and visible spectrum) range of electro-magnetic(em) radiation.

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Advancements in all-solid-state hybrid solar cells based on organometal halide perovskites

Materials Horizons ◽

10.1039/c4mh00236a ◽

2015 ◽

Vol 2 (4) ◽

pp. 378-405 ◽

Cited By ~ 91

Author(s):

Shaowei Shi ◽

Yongfang Li ◽

Xiaoyu Li ◽

Haiqiao Wang

Keyword(s):

Diffusion Length ◽

Power Conversion ◽

Hybrid Solar Cells ◽

Research Attention ◽

Direct Band Gap ◽

The Past ◽

Considerable Research ◽

Direct Band ◽

Halide Perovskites ◽

Photovoltaic Technologies

Over the past several years, organic–inorganic hybrid perovskites have gained considerable research attention due to their direct band gap, large absorption coefficient, ambipolar diffusion and long carrier diffusion length, and have revolutionized the prospects of emerging photovoltaic technologies, with the highest power conversion efficiency of over 19% achieved under laboratory conditions.

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