Indium-doped ZnOas efficient photosensitive material for sunlight driven hydrogen generation and DSSC applications: integrated experimental and computational approach

Electricity generation using simple and cheap dye-sensitized solar cells and photocatalytic water splitting to produce future fuel, hydrogen, directly under natural sunlight fascinated the researchers worldwide. Herein, synthesis of indium-doped wurtzite ZnO nanostructures with varying molar percentage of indium from 0.25 to 3.0% with concomitant characterization indicating wurtzite structure is reported. The shift of (002) reflection plane to higher 2θ degree with increase in indium-doping thus is a clear evidence of doping of indium in zinc oxide nanoparticles. Surface morphological as well as microstructural studies of In@ZnO exhibited generation of ZnO nanoparticles and nanoplates of diameter 10–30 nm. The structures have been correlated well using computational density functional (DFT) studies. Diffuse reflectance spectroscopy depicted the extended absorbance of these materials in the visible region. Hence, the photocatalytic activity towards hydrogen generation from water under natural sunlight as well as efficient DSSC fabrication of these newly synthesized materials has been demonstrated. In-doped ZnO exhibited enhanced photocatalytic activity towards hydrogen evolution (2465 μmol/h/g) via water splitting under natural sunlight. DSSC fabricated using 2% In-doped ZnO exhibited an efficiency of 3.46% which is higher than other reported In-doped ZnO based DSSCs.

     

Two New 3D Metal-Organic Frameworks Constructed by Polycarboxylate and N-Donor Ligands: Crystal Structure,Photocatalytic Performances,and DFT Calculation

Russian Journal of Coordination Chemistry - Two new metal-organic frameworks, [Zn(Bdc)(Bip)?H2O] (I) and {[Cd2(Btc)2(H2O)2](H2Bib)· 6H2O} (II) (H2Bdc = 1,3-benzenedicarboxylic acid,...     

Mononuclear High-spin Octahedral Cobalt(II) Complex with Positive Axial Magnetic Anisotropy: Synthesis,Crystal Structure,and DFT Studies

This article outlines the magnetic features of a new six–coordinate high-spin cobalt(II) complex cis-[Co^II(tmphen)₂(NCS)₂] ( 1 ) achieved via the reactions of cobalt(II) thiocyanate with 3,4,7,8-tetramethyl-1,10-phenanthroline. The complex 1 was thoroughly characterized by different analytical and spectroscopic techniques and further confirmed by single X-ray crystal diffraction pattern. Complex 1 is a neutral molecule and adopt highly distorted six-coordinate CoN₆ octahedral coordination sphere surrounded by two thiocyanate N atoms in cis locations and the equatorial plane is occupied by two imine N atoms from the two tmphen ligand while the remaining two imine N atoms reside in the axial positions. Magnetic susceptibility data of complex 1 revealed that the χ_ΜT values decrease significantly to a value of 1.49 cm³ · K · mol^–1 at 2.0 K on decreasing temperatures below 100 K, mainly ascribed to the significant spin–orbit coupling (SOC) of six-coordinate Co^II ions. Furthermore, a field-dependence measurement was performed at 2 K, which shows a positive curvature up to 27 kOe, while it becomes linear up to 2.01 Nμ_B, which authenticated the fact that only the lowest Kramers doublet of ground state is appreciably populated.     

N-methylferrocenyl-N-ethylhydroxy ammonium nitrate: synthesis,characterization, and sensitizer in dye-sensitized solar cells

Transition Metal Chemistry - A new ferrocene-containing hydronitrate salt with formula N-methylferrocenyl-N-ethylhydroxy ammonium nitrate has been synthesized and characterized using microanalyses,...     

Synthesis of new chiral heterocyclic Schiff base modulated Cu(II)/Zn(II) complexes: their comparative binding studies with CT-DNA, mononucleotides and cleavage activity

New Schiff base ligand L derived from the condensation reaction of 2-amino-3-formylchromone with (R)-2-amino-2-phenylethanol was synthesized and characterized which involves combination element of ammine functionality and naturally occurring heterocyclic chromone, 4H-benzopyran-4-one. Subsequently, their complexes 1 and 2 with Cu(NO?)? and Zn(NO?)?, respectively were prepared. The DNA binding studies of the ligand L and complexes 1 and 2 with CT-DNA as compared to classical anticancer drug cisplatin were carried out by employing different optical methods viz, UV-vis, fluorescence, circular dichroism and viscosity measurements. Furthermore, the absorption studies, 1H and 31P with mononucleotides were also monitored to examine the base specific interactions of the transition metal complexes which revealed a higher propensity of copper(II) complex 1 for 5'-GMP while for zinc(II) complex 2 towards 5'-TMP involving groove binding mechanism of the complexes towards DNA. The complex 1 exhibits a remarkable DNA cleavage activity with pBR322 DNA in presence of different activators and cleavage reaction involves various oxygen species suggesting the involvement of active oxygen species for the DNA scission.     

Dual beam method for laser welding of galvanized steel: Experimentation and prospects

Laser welding of zinc-coated steel sheets in lap configuration poses a challenging problem, because of the zinc vapours spoiling the quality of the weld. In continuation to the earlier work, the novel solution of dual laser beam method for lap welding of galvanized steel sheets is discussed here in view of the recently obtained observations and ensuing concerns. In this method the precursor beam cuts a slot, thus making an exit path for the zinc vapours, while the second beam performs the needed welding. The metallurgical analysis of the welds is encouraging showing absence of zinc in the welded area. In the current work on this technique, new experimental results have been obtained verifying the earlier observations. Along with this, the possibility of using a transversely split-up beam for the welding purposes with this approach is discussed and analyzed in this paper. This new technique is expected to be very useful in prospective industrial applications requiring higher welding throughput along with the needed quality.     

Tertiary phosphine-appended transition metal ferrocenyl dithiocarbamates: Syntheses,Hirshfeld surface,and electrochemical analyses

Five new heteroleptic complexes of Cu(I), Ag(I), and Ni(II) having formulae [Cu₃(dtc)₂(dppf)₂]PF₆ ( Cu-I ), [Cu₃(dtc)₂(dppe)₂]PF₆ ( Cu-II ), [Cu(PPh₃)₂(dtc)] ( Cu-III ), [Ag₃(dtc)₂(PPh₃)₂]NO₃ ( Ag-I ), and [Ni(dtc)(dppf)]PF₆ ( Ni-I ) (dtc = N-ethanol-N-methylferrocenyl-dithiocarbamate; dppf = 1,1′-bis(diphenylphosphino)ferrocene; dppe = 1,1′-bis(diphenylphosphino)ethane; PPh₃ = tripheylphosphine) have been synthesized and characterized using elemental analysis, Fourier-transform infrared, multinuclear nuclear magnetic resonance, UV–Vis spectroscopy, and single-crystal X-ray diffraction. The single-crystal X-ray diffraction studies indicate that Ag-I forms a rare trinuclear cluster in which the geometry around the two silver centers Ag1 and Ag3 is distorted tetrahedral, whereas the third silver center Ag2 shows a distorted trigonal planar geometry. The Ni-I complex has a distorted square-planar geometry around the Ni center. In addition, a side product [Ag₂{S₂(dppf)₂}] ( Ag-II ) was obtained during an attempt to synthesize [Ag(dppf)(dtc)], where the two Ag centers are bridged by two sulfido centers and coordinated with two phosphorus centers of the dppf ligand to give rise to a distorted tetrahedral geometry. The solid-state structures of Ag-I , Ni-I , and Ag-II are stabilized by a variety of weak interactions. The nature of these interactions has been addressed with the help of Hirshfeld surface analyses. In addition, the weak argentophilic interaction in Ag-I and Ag-II have been studied using quantum theory of atoms in molecules and natural bond orbital calculations. The electrochemical properties of the complexes have been investigated using cyclic voltammetry, where Cu-I and Cu-II exhibited two quasi-reversible waves, whereas Cu-III , Ag-I , Ag-II , and Ni-I exhibited only one quasi-reversible peak.     

Evaluating Zn‐Porphyrin‐Based Near‐IR‐Sensitive Non‐Fullerene Acceptors for Efficient Panchromatic Organic Solar Cells

Porphyrin‐based non‐fullerene acceptors (NFAs) have shown pronounced potential for assembling low‐bandgap materials with near‐infrared (NIR) characteristics. Herein, panchromatic‐type porphyrin‐based molecules (POR1–POR5) are proposed by modulating end‐capped acceptors of a highly efficient porphyrin‐based NFA PORTFIC(POR) for organic solar cells (OSCs). Quantum chemical structure‐property relationship has been studied to discover photovoltaic and optoelectronic characteristics of POR1–POR5. Results show that optoelectronic properties of the POR1–POR5 are better in all aspects when compared with the reference POR. All proposed NFAs particularly POR5 proved to be the preferable porphyrin‐based NIR sensitive NFA for OSCs applications owing to lower energy gap (1.56 eV), transition energy (1.11 eV), binding energy (E_b =0.986 eV), electron mobility (λ_e=0.007013E_h ), hole mobility (λ_h =0.004686 E_h), high λ_max =1116.27 nm and open‐circuit voltage (V_oc =1.96 V) values in contrast to the reference POR and other proposed NFAs. This quantum chemical insight provides sufficient evidence about excellent potential of the proposed porphyrin‐based NIR sensitive NFA derivatives for their use in OSCs.     

De novo design of chiral organotin cancer drug candidates: validation of enantiopreferential binding to molecular target DNA and 5'-GMP by UV-visible, fluorescence, (1)H and (31)P NMR

N,N-bis[(R-/S-)-1-benzyl-2-ethoxyethane] tin (IV) complexes were synthesized by applying de novo design strategy by the condensation reaction of (R-/S-)2-amino-2-phenylethanol and dibromoethane in presence of dimethyltin dichloride and thoroughly characterized by elemental analysis, conductivity measurements, IR, ESI-MS, (1)H, (13)C and (119)Sn, multinuclear NMR spectroscopy and XRD study. Enantioselective and specific binding profile of R-enantiomer 1 in comparison to S-enantiomer 2 with ultimate molecular target CT-DNA was validated by UV-visible, fluorescence, circular dichroism, (1)H and (31)P NMR techniques. This was further corroborated well by interaction of 1 and 2 with 5'-GMP.     

In silico fight against novel coronavirus by finding chromone derivatives as inhibitor of coronavirus main proteases enzyme

Structural Chemistry - Novel coronavirus, 2019-nCoV is a danger to the world and is spreading rapidly. Very little structural information about 2019-nCoV make this situation more difficult for drug...