Stereochemistry of lead(II) complexes with oxygen donor ligands

Pb2Cd(SeO3)2X2 (X = Cl and Br): two halogenated selenites with phase matchable second harmonic generation

The second harmonic generation (SHG) efficiencies of Pb₂Cd(SeO₃)₂X₂ (X = Cl and Br) are higher than that of commercial KDP (KH₂PO₄) and their laser damage thresholds are 30 times more than that of AGS (AgGaS₂).

Efficient X-ray scintillating lead(ii)-based MOFs derived from rigid luminescent naphthalene motifs

The synergistic effects of heavy metal Pb(ii) centers and rigid organic ligands afford Pb(ii)-based MOF scintillator candidates for X-ray detection.

A tetranuclear nickel/lead complex with a salen type Schiff base: synthesis, structure and exploration of photosensitive Schottky barrier diode behaviour

A tetranuclear nickel(ii)/lead(ii) complex has been synthesized and characterized. The complex based device behaves as a Schottky diode. The charge transfer kinetics of the complex is enhanced after light soaking.

Formation of a tetranuclear supramolecule via non-covalent Pb⋯Cl tetrel bonding interaction in a hemidirected lead(ii) complex with a nickel(ii) containing metaloligand

A hetero-nuclear nickel(ii)/lead(ii) complex has been synthesized and characterized. The tetrel bonding interactions established between the σ-hole at the hemi-coordinated lead(ii) and the electron rich chlorido ligand has been analyzed by DFT study.

Fabrication of an Active Electronic Device Using a Hetero-bimetallic Coordination Polymer

A nickel(II)/lead(II) coordination polymer [(NCS)Pb(H₂O)LNi(NCS)]_n {H₂L = N,N'-bis(3-methoxysalicylidene)propane-1,3-diamine} has been synthesized and characterized. The band gap (3.18 eV) calculated from Tauc's plot suggests the semiconducting nature of the complex. The material has a photosensitivity of 5.76, indicating its applicability in the fabrication of photosensitive devices. The complex has been successfully applied in a technologically challenging thin-film photosensitive Schottky device.

Metal ion coordination enhancing quantum efficiency of ligand phosphorescence in a double-stranded helical chain coordination polymer of Pb2+ with nicotinic acid

A new 1D phosphorescence coordination polymer (CP) [Pb2O(C6H4NO2)2]n (1; C6H4NO2 = nicotinate) was synthesized by a solvothermal reaction and PbO was used as a Pb(ii) source instead of traditional Pb(ii) salts. This remarkably thermal-stable CP crystallizes in the space group I41/a. In the crystal structure of 1, two different Pb(ii) ions show a five-coordinated and hemidirected coordination geometry, two nonequivalent nicotinate ligands link to Pb(ii) ions in μ2-η1:η1 and μ4-η2:η2 modes, and the hemidirected coordination polyhedra of Pb(ii) form a helical lead-oxide chain via an edge-sharing fashion along the c-axis. Under ambient conditions, 1 emits cyan ligand-based phosphorescence with an absolute quantum yield as high as 59.4% and a lifetime of 9.86 ms under UV-light irradiation. Under the same conditions, nicotinic acid emits simultaneously fluorescence and phosphorescence with a total absolute quantum yield of 4.8%. The great enhancement of phosphorescence quantum yield in 1, regarding nicotinic acid, is assigned to the heavy atom effect of Pb(ii) and negligible ππ interaction between pyridyl rings. Noticeably, the vibronic fine structure is observed in the emission spectrum of 1 at room temperature. Additionally, 1 shows thermochromic behavior, and such functionality probably has realistic application in the field of temperature detection.

PbCdF(SeO3)(NO3): A Nonlinear Optical Material Produced by Synergistic Effect of Four Functional Units

A new nonlinear optical material, the first fluoride selenite nitrate PbCdF(SeO₃)(NO₃), was successfully synthesized by traditional solid state reactions. This compound crystallizes in the polar space group of Pca2₁, and its structure features a novel 2D layered structure consisting of 1D lead nitrate chains and 2D cadmium selenite layers. PbCdF(SeO₃)(NO₃) exhibits a phase-matchable SHG efficiency of about 2.6 times that of KDP and a wide band gap of 4.42 eV. Its laser damage threshold was measured to be 135.6 MW/cm², which is comparative to that of the reported Li₇(TeO₃)₃F with a short ultraviolet cutoff edge. Theoretical calculation confirmed that the synergistic effects of all the four functional units make PbCdF(SeO₃)(NO₃) a remarkable SHG material.

The 3 D Structure of Twisted Benzo[ghi]perylene-Triimide Dimer as a Non-Fullerene Acceptor for Inverted Perovskite Solar Cells

Here, we introduced benzo[ghi]perylenetriimide (BPTI) derivatives including monomer and twisted dimer (t-BPTI) as an alternative electron-transport layer (ETL) material to replace the commonly used PC₆₁ BM in inverted planar heterojunction perovskite solar cells (PSCs). Moreover, the double ETL was applied in our PSCs with structure of glass/ITO/PEDOT:PSS/perovskite/BPTI/C₆₀ or PDI-C4/BCP/Al. The use of a double ETL structure can effectively eliminate the leakage current. The devices with the t-BPTI/C₆₀ double ETL yield an average power conversion efficiency of 10.73 % and a maximum efficiency of 11.63 %. The device based on the complete non-fullerene electron acceptors of t-BPTI/PDI-C4 as double ETL achieved maximum efficiency of 10.0 %. Moreover, it was found that the utilization of alloy t-BPTI+BPTI as ETL can effectively reduce the hysteresis effect of PSCs. The results suggest that BPTI-based electron-transport materials are potential alternatives for widely used fullerene acceptors in PSCs.

Non-covalent tetrel bonding interactions in hemidirectional lead(ii) complexes with nickel(ii)-salen type metalloligands

Tetrel bonding interactions have been investigated in hetero-dinuclear nickel(ii)/lead(ii) complexes using MEP and DFT calculations.

Lead encapsulation by a golden clamp through multiple electrostatic, metallophilic, hydrogen bonding and weak interactions

Complex [{Pb(HBpz₃)}{Au₃(o-C₆BrF₄)₃(HBpz₃)}] consists of a host–guest heterometallic system built up through a plethora of interactions including ionic and dispersive forces.

On the importance of Pb⋯X (X = O, N, S, Br) tetrel bonding interactions in a series of tetra- and hexa-coordinated Pb(ii) compounds

We study Pb⋯X (X = N, S, Br) tetrel bonding interactions in a series of tetra- and hexa-coordinated Pb(ii) compounds that exhibit hemidirectional coordination.

Structural chemistry of fluoride and mixed-ligand fluoride complexes of gallium(III)

This article covers the structural chemistry of fluoride and mixed-ligand fluoride complexes of gallium(III), discusses more than 140 known crystal structures of anionic fluoride and mixed-ligand fluoride complexes and continues the discussion initiated in previous reviews dedicated to the stereochemistry and structural chemistry of group III–V metals fluoride complexes. Most of these structures have been established by single-crystal X-ray diffraction techniques, but some were characterized by powder X-ray diffraction methods. This paper offers a discussion of the geometry of gallium and outer sphere cation coordination polyhedra, the association of gallium atoms in dimer and polymer formations, types of cation-anion interactions, and their contributions in actual three-dimensional crystal structures. The structural information has been compiled in a single table containing phase compositions and the corresponding standard crystallographic data (such as crystal system, space group, unit cell parameters, number of formula units per cell [Z], reliability factors [R1], Ga-F, and Ga-O bond lengths).

Synthesis and characterization of a new nano lead(II) 0-D coordination supramolecular compound: A precursor to produce pure phase nano-sized lead(II) oxide

Nano-structure of a new 0D Pb(II) coordination supramolecular compound, [Pb₄(8-Quin)₆](ClO₄)₂(1), L=8-HQuin=8-hydroxyquinolin ligand has been synthesized by use of a sonochemical process and characterized by scanning electron microscopy (SEM), X-ray powder diffraction (XRPD), Fourier transform infrared spectroscopy (FTIR) and elemental analyses. The structure of compound 1 was determined by single-crystal X-ray diffraction. The single crystal X-ray data of compound 1 implies that the Pb⁺² ions are five coordinated. Each lead atom is coordinated to nitrogen and oxygen atoms of 8-hydroxyquinolin ligand. Topological analysis shows that the compound 1 is 1,2,3,4,4M12-1net. Nanoparticles of lead(II) oxide have been prepared by calcination of lead(II) coordination polymer at 500°C that were characterized by scanning electron microscopy (SEM), X-ray powder diffraction (XRPD) and IR spectroscopy.

Volatile heterometallics: structural diversity of Pd-Pb β-diketonates and correlation with thermal properties

Volatile heterobimetallics based on Pb(ii) hexafluoroacetylacetonate as a host material and a range of Pd(ii) complexes containing both various donor atoms and terminal substituents in the β-diketonate ligand have been studied to trace the influence of the nature of the initial monometallic complexes on the structure, composition and thermal properties of heterobimetallic compounds. The structural variety and stoichiometry of the heterobimetallic compounds are caused by various combinations of the competing donor-acceptor interactions between the constituting monometallic moieties. The major structure forming factor is the metallophilic interaction between Pd and Pb atoms resulting in polynuclear structures with a specific topology. The structural motif (discrete or polymeric) for the compounds significantly depends on the structure and composition of the initial monometallic complexes. The approach for explaining and predicting the thermal stability of these compounds is proposed by using their structural data and the results of quantum chemistry calculations.

Synthesis and crystal structure of catena-poly[(μ2-nicotinato-κ2 O,O′: κ1 N)-(nitrato-κ1 O)-(bis(2-benzimidazol-ylmethyl)amine-κ3 N,N′,N′′)lead(II)], C22H18N7O5Pb

C22H18N7O5Pb, triclinic, P1̅ (no. 2), a = 7.7446(17) Å, b = 16.914(3) Å, c = 17.726(3) Å, α = 72.451(6)°, β = 86.900(6)°, γ = 88.098(7)°, V = 2210.3(7) Å3, Z = 4, R gt(F) = 0.0379, wR ref(F 2) = 0.0751, T = 153 K.

Anion-driven tetrel bond-induced engineering of lead(ii) architectures with N′-(1-(2-pyridyl)ethylidene)nicotinohydrazide: experimental and theoretical findings

A new series of Pb^II coordination compounds was assembled with the N′-(1-(2-pyridyl)ethylidene)nicotinohydrazide ligand and various auxiliary inorganic counterions.

Blended additive manipulated morphology and crystallinity transformation toward high performance perovskite solar cells

The morphology and crystallinity of MAPbI₃ thin films were regulated using blended-additive engineering for high performance perovskite solar cells.

Systematic synthesis of pectin-g-(sodium acrylate-co-N-isopropylacrylamide) interpenetrating polymer network for superadsorption of dyes/M(ii): determination of physicochemical changes in loaded hydrogels

Superadsorbent hydrogel with excellent physicochemical properties is used for mere/synergic chemisorption of dyes and M(ii).

Improved Performance and Stability of Inverted Planar Perovskite Solar Cells Using Fulleropyrrolidine Layers

Inverted planar structure perovskite solar cells (PSCs), due to their low-temperature precessing and lack of hysteretic problems, are attracting increased attention by researchers around the world. Fullerene derivatives are the most widely used electron transport materials (ETMs) in inverted planar perovskite solar cells, especially [6,6]-phenyl-C₆₁-butyric acid methylester (PC₆₁BM), which exhibits very good performance. However, to the best of our knowledge, the influence of adducts on fullerene-based PSCs performance has not been fully explored to date. In this work, two fullerene derivatives, 2,5-(dimethyl ester) C₆₀ fulleropyrrolidine (DMEC₆₀) and the analogous C₇₀ derivative (DMEC₇₀), were synthesized in high yield via a 1,3-dipolar cycloaddition reaction at room temperature and incorporated into CH₃NH₃PbI₃ perovskite solar cells as electron transport materials. Possibly because the attached pyrrolidine ester groups are able to coordinate with the perovskite layer, the devices based on DMEC₆₀ and DMEC₇₀ achieved power conversion efficiencies (PCE) of 15.2% and 16.4%, respectively. Not only were both devices' efficiencies higher than those based on PC₆₁BM and PC₇₁BM, but their stabilities were also higher than those for PCBM-based devices. The results suggest that DMEC₆₀ and DMEC₇₀ are better alternatives than PC₆₁BM and PC₇₁BM for the ETMs in PSCs.

On the importance of tetrel bonding interactions in lead(ii) complexes with (iso)nicotinohydrazide based ligands and several anions

We report four Pb(ii) complexes with (iso)nicotinohydrazide based ligands exhibiting relevant tetrel bonding interactions that have been characterized using DFT calculations.

Inorganic–organic hybrid materials based on PbBr2 and pyridine–hydrazone blocks – structural and theoretical study

A new series of lead(ii) coordination polymers was generated from PbBr₂ and various pyridine–hydrazone blocks; their detailed structural, topological and theoretical analysis was performed.

Microstructures of Organometal Trihalide Perovskites for Solar Cells: Their Evolution from Solutions and Characterization

The use of organometal trihalide perovskites (OTPs) in perovskite solar cells (PSCs) is revolutionizing the field of photovoltaics, which is being led by advances in solution processing of OTP thin films. First, we look at fundamental phenomena pertaining to nucleation/growth, coarsening, and microstructural evolution involved in the solution-processing of OTP thin films for PSCs from a materials-science perspective. Established scientific principles that govern some of these phenomena are invoked in the context of specific literature examples of solution-processed OTP thin films. Second, the nature and the unique characteristics of OTP thin-film microstructures themselves are discussed from a materials-science perspective. Finally, we discuss the challenges and opportunities in the characterization of OTP thin films for not only gaining a deep understanding of defects and microstructures but also elucidating classical and nonclassical phenomena pertaining to nucleation/growth, coarsening, and microstructural evolution in these films. The overall goal is to have deterministic control over the solution-processing of tailored OTP thin films with desired morphologies and microstructures.

Design of Lead(II) Metal-Organic Frameworks Based on Covalent and Tetrel Bonding

Three solid materials, [Pb(HL)(SCN)2 ]⋅CH3 OH (1), [Pb(HL)(SCN)2 ] (2), and [Pb(L)(SCN)]n (3), were obtained from Pb(SCN)2 and an unsymmetrical bis-pyridyl hydrazone ligand that can act both as a bridging and as a chelating ligand. In all three the lead center is hemidirectionally coordinated and is thus sterically optimal for participation in tetrel bonding. In the crystal structures of all three compounds, the lead atoms participate in short contacts with thiocyanate sulfur or nitrogen atoms. These contacts are shorter than the sums of the van der Waals radii (3.04-3.47 Å for Pb⋅⋅⋅S and 3.54 Å for Pb⋅⋅⋅N) and interconnect the covalently bonded units (monomers, dimers, and 2D polymers) into supramolecular assemblies (chains and 3D structures). DFT calculations showed these contacts to be tetrel bonds of considerable energy (6.5-10.5 kcal mol(-1) for Pb⋅⋅⋅S and 16.5 kcal mol(-1) for Pb⋅⋅⋅N). A survey of structures in the CSD showed that similar contacts often appear in crystals of Pb(II) complexes with regular geometries, which leads to the conclusion that tetrel bonding plays a significant role in the supramolecular chemistry of Pb(II) .

Confined Flocculation of Ionic Pollutants by Poly(L-dopa)-Based Polyelectrolyte Complexes in Hydrogel Beads for Three-Dimensional, Quantitative, Efficient Water Decontamination

The development of simple and recyclable adsorbents with high adsorption capacity is a technical imperative for water treatment. In this work, we have successfully developed new adsorbents for the removal of ionic pollutants from water via encapsulation of polyelectrolyte complexes (PECs) made from positively charged poly(allylamine hydrochloride) (PAH) and negatively charged poly(l-3,4-dihydroxyphenylalanine) (PDopa), obtained via the self-polymerization of l-3,4-dihydroxyphenylalanine (l-Dopa). Given the outstanding mass transport through the hydrogel host matrixes, the PDopa-PAH PEC guests loaded inside can effectively and efficiently remove various ionic pollutants, including heavy metal ions and ionic organic dyes, from water. The adsorption efficiency of the PDopa-PAH PECs can be quantitatively correlated to and tailored by the PDopa-to-PAH molar ratio. Because PDopa embodies one catechol group, one carboxyl group, and one amino group in each repeating unit, the resulting PDopa-PAH PECs exhibit the largest capacity of adsorption of heavy metal ions compared to available adsorbents. Because both PDopa and PAH are pH-sensitive, the PDopa-PAH PEC-loaded agarose hydrogel beads can be easily and completely recovered after the adsorption of ionic pollutants by adjusting the pH of the surrounding media. The present strategy is similar to the conventional process of using PECs to flocculate ionic pollutants from water, while in our system flocculation is confined to the agarose hydrogel beads, thus allowing easy separation of the resulting adsorbents from water.