Structural and Electronic Impact of an Asymmetric Organic Ligand in Diammonium Lead Iodide Perovskites

Using spectrophotometric titration technique, the processes of complex formation of some phenylazo-derivatives of methylphloroglucinol (MPG) containing hydroxo-, nitro- and nitroso-substituents were studied. The spectral criteria of neutral and ionized forms of the organic ligands in their different tautomeric forms were determined.It was detected that the complex formation is accompanied by formation of one or two chelate cycles which involve azo- or nitroso-fragments and neighboring OH-groups of the organic ligands. Different types of coordination lead to different changes in the electronic absorption spectra.The DFT-B3LYP modeling of a Ni(II) complex of α-hydroxyphenylazo MPG established the most probable coordination mode of the organic ligand: tridentate chelating dianion, distorted square coordination of Ni-cations including one water molecule. The theoretical results are in a good accordance with the experimental data.

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Site-Specific Protein Covalent Attachment to Nanotubes and Its Electronic Impact on Single Molecule Function

10.26434/chemrxiv.7798973.v1 ◽

2019 ◽

Author(s):

Adam Beachey ◽

Harley Worthy ◽

William David Jamieson ◽

Suzanne Thomas ◽

Benjamin Bowen ◽

...

Keyword(s):

Single Molecule ◽

Fluorescent Protein ◽

Functional Integration ◽

Attachment Site ◽

Covalent Attachment ◽

Great Promise ◽

Functional Coupling ◽

Phenyl Azide ◽

Electronic Impact ◽

Protein Attachment

<p>Functional integration of proteins with carbon-based nanomaterials such as nanotubes holds great promise in emerging electronic and optoelectronic applications. Control over protein attachment poses a major challenge for consistent and useful device fabrication, especially when utilizing single/few molecule properties. Here, we exploit genetically encoded phenyl azide photochemistry to define the direct covalent attachment of three different proteins, including the fluorescent protein GFP, to carbon nanotube side walls. Single molecule fluorescence revealed that on attachment to SWCNTs GFP’s fluorescence changed in terms of intensity and improved resistance to photobleaching; essentially GFP is fluorescent for much longer on attachment. The site of attachment proved important in terms of electronic impact on GFP function, with the attachment site furthest from the functional center having the larger effect on fluorescence. Our approach provides a versatile and general method for generating intimate protein-CNT hybrid bioconjugates. It can be potentially applied easily to any protein of choice; attachment position and thus interface characteristics with the CNT can easily be changed by simply placing the phenyl azide chemistry at different residues by gene mutagenesis. Thus, our approach will allow consistent construction and modulate functional coupling through changing the protein attachment position.</p>

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Properties of methylammonium lead iodide peerovskite single crystals

Журнал структурной химии ◽

10.26902/jsc20170813 ◽

2017 ◽

Vol 58 (8) ◽

Author(s):

E. S. Yudanova ◽

◽

T. A. Duda ◽

O. E. Tereshchenko ◽

O. I. Semenova ◽

...

Keyword(s):

Single Crystals ◽

Lead Iodide ◽

Methylammonium Lead Iodide

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Ferroelectric domains in methylammonium lead iodide perovskite solar cells

10.29363/nanoge.fallmeeting.2018.167 ◽

2018 ◽

Author(s):

Holger Röhm ◽

Tobias Leonhard ◽

Michael J. Hoffmann ◽

Alexander Colsmann

Keyword(s):

Solar Cells ◽

Perovskite Solar Cells ◽

Lead Iodide ◽

Ferroelectric Domains ◽

Methylammonium Lead Iodide

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The impact of metal ions doping on the defect chemistry of methylammonium lead iodide

10.29363/nanoge.iperop.2019.039 ◽

2018 ◽

Author(s):

Nga Phung ◽

Antonio Abate ◽

Daniele Meggiolaro ◽

Filippo De Angelis ◽

Roberto Felix Duarte ◽

...

Keyword(s):

Metal Ions ◽

Defect Chemistry ◽

Lead Iodide ◽

Methylammonium Lead Iodide ◽

The Impact

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Guanidinium/Methylammonium Lead Iodide Perovskite: An Unexplored Avenue for Stable and 20% Efficient Solar Cells

10.29363/nanoge.hopv.2018.091 ◽

2018 ◽

Author(s):

Gustavo de Miguel ◽

Alexander Davis Jodlowski ◽

Cristina Roldán-Carmona ◽

Luis Camacho Delgado ◽

Mohammad Khaja Nazeeruddin

Keyword(s):

Solar Cells ◽

Lead Iodide ◽

Methylammonium Lead Iodide

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Fundamental Efficiency Limit of Lead Iodide Perovskite Solar Cells

10.29363/nanoge.fallmeeting.2018.001 ◽

2018 ◽

Author(s):

Luis Pazos-Outon ◽

T. Patrick Xiao ◽

Eli Yablonovitch

Keyword(s):

Solar Cells ◽

Perovskite Solar Cells ◽

Lead Iodide

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Continuous Precipitation of Lead Iodide

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19941503 ◽

1994 ◽

Vol 59 (7) ◽

pp. 1503-1510

Author(s):

Stanislav Žáček ◽

Jaroslav Nývlt

Keyword(s):

Growth Rate ◽

Particle Size ◽

Crystal Size ◽

Crystal Growth Rate ◽

Laboratory Model ◽

Lead Iodide ◽

Secondary Nucleation ◽

Equimolar Ratio ◽

Continuous Precipitation ◽

The Mean

Lead iodide was precipitated from aqueous solutions of 0.015 - 0.1 M Pb(NO3)2 and 0.03 - 0.2 M KI in the equimolar ratio using a laboratory model of a stirred continuous crystallizer at 22 °C. After reaching the steady state, the PbI2 crystal size distribution was measured sedimentometrically and the crystallization kinetics was evaluated based on the mean particle size. Both the linear crystal growth rate and the nucleation rate depend on the specific output of the crystallizer. The system crystallization constant either points to a significant effect of secondary nucleation by the mechanism of contact of the crystals with the stirrer blade, or depends on the concentrations of the components added due to the micromixing mechanism.

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Batch Precipitation of Lead Iodide

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19941301 ◽

1994 ◽

Vol 59 (6) ◽

pp. 1301-1304

Author(s):

Jaroslav Nývlt ◽

Stanislav Žáček

Keyword(s):

Aqueous Solution ◽

Particle Size ◽

Particle Size Distribution ◽

Size Distribution ◽

Crystal Size ◽

Lead Nitrate ◽

Lead Iodide ◽

Constant Rate ◽

Mean Size ◽

The Mean

Lead iodide was precipitated by a procedure in which an aqueous solution of potassium iodide at a concentration of 0.03, 0.10 or 0.20 mol l-1 was stirred while an aqueous solution of lead nitrate at one-half concentration was added at a constant rate. The mean size of the PbI2 crystals was determined by evaluating the particle size distribution, which was measured sedimentometrically. The dependence of the mean crystal size on the duration of the experiment exhibited a minimum for any of the concentrations applied. The reason for this is discussed.

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Effects of 5-Ammonium Valeric Acid Iodide as Additive on Methyl Ammonium Lead Iodide Perovskite Solar Cells

Nanomaterials ◽

10.3390/nano10122512 ◽

2020 ◽

Vol 10 (12) ◽

pp. 2512

Author(s):

Daming Zheng ◽

Changheng Tong ◽

Tao Zhu ◽

Yaoguang Rong ◽

Thierry Pauporté

Keyword(s):

Solar Cells ◽

Perovskite Solar Cells ◽

Single Crystal Silicon ◽

Mesoporous Structure ◽

Valeric Acid ◽

Electrical Impedance Spectroscopy ◽

Lead Iodide ◽

Crystal Silicon ◽

Time Resolved ◽

Hole Transporting

During the past decade, the power conversion efficiency (PCE) of perovskite solar cells (PSCs) has risen rapidly, and it now approaches the record for single crystal silicon solar cells. However, these devices still suffer from a problem of stability. To improve PSC stability, two approaches have been notably developed: the use of additives and/or post-treatments that can strengthen perovskite structures and the use of a nontypical architecture where three mesoporous layers, including a porous carbon backcontact without hole transporting layer, are employed. This paper focuses on 5-ammonium valeric acid iodide (5-AVAI or AVA) as an additive in methylammonium lead iodide (MAPI). By combining scanning electron microscopy (SEM), X-ray diffraction (XRD), time-resolved photoluminescence (TRPL), current–voltage measurements, ideality factor determination, and in-depth electrical impedance spectroscopy (EIS) investigations on various layers stacks structures, we discriminated the effects of a mesoscopic scaffold and an AVA additive. The AVA additive was found to decrease the bulk defects in perovskite (PVK) and boost the PVK resistance to moisture. The triple mesoporous structure was detrimental for the defects, but it improved the stability against humidity. On standard architecture, the PCE is 16.9% with the AVA additive instead of 18.1% for the control. A high stability of TiO2/ZrO2/carbon/perovskite cells was found due to both AVA and the protection by the all-inorganic scaffold. These cells achieved a PCE of 14.4% in the present work.

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