Inexpensive Hole‐Transporting Materials Derived from Tröger's Base Afford Efficient and Stable Perovskite Solar Cells

The synthesis of three enamine hole‐transporting materials (HTMs) based on Tröger's base scaffold are reported. These compounds are obtained in a three‐step facile synthesis from commercially available materials without the need of expensive catalysts, inert conditions or time‐consuming purification steps. The best performing material, HTM3, demonstrated 18.62 % PCE in PSCs, rivaling spiro‐OMeTAD in efficiency, and showing markedly superior long‐term stability in non‐encapsulated devices. In dopant‐free PSCs, HTM3 outperformed spiro‐OMeTAD by a factror of 1.6. The high glass‐transition temperature (T_g=176 °C) of HTM3 also suggests promising perspectives in device applications.     

Cu (II)‐β‐cyclodextrin complex stabilized on magnetic nanoparticles: A retrievable hybrid promoter for green synthesis of spiropyrans

The magnetic core of manganese ferrite (MnFe₂O₄) nanoparticles has a significant stability in comparison with ferrite (Fe₃O₄) nanoparticles. The unique supramolecular properties of β‐cyclodextrin (β‐CD), such as hydrophobic cavity, hydrophilic exterior and ‐OH functional groups, make it a good candidate for functionalization and catalytic application. So, a surface‐modified magnetic solid support with the Cu (II)‐β‐CD complex was prepared. The structure of nanoparticles was characterized by Fourier transform‐infrared spectroscopy, X‐ray powder diffraction, thermogravimetric analysis, vibrating‐sample magnetometry, inductively coupled plasma‐optical emission spectrometry and scanning electron microscope analyses. The catalytic activity of these nanoparticles was investigated in the synthesis of spiropyrans and high yields of desired products obtained under green media. Some advantages of this novel catalyst for this reaction are high yields, short reaction times, green solvent and conditions, easy workup procedure, negligible copper leaching, reusability without a significant diminish in catalytic efficiency, and simple separation of nanocatalyst by using an external magnet alongside the environmental compatibility and sustainability.     

Synthesis and characterization of Co (III) salen complex immobilized on cobalt ferrite‐silica nanoparticle and their application in the synthesis of spirooxindoles

The preparation, characterization and catalytic application of Co (III) salen complex loaded on cobalt ferrite‐silica nanoparticle [CoFe₂O₄@SiO₂@ Co (III) salen complex] are described. Co (III) salen complex loaded on ferrite cobalt‐silica nanoparticles is characterized by transmission electron microscopy, scanning electron microscopy coupled with energy‐dispersive X‐ray, vibrating‐sample magnetometer and Fourier transform‐infrared analyses. The thermal stability of the material is also determined by thermal gravimetric analysis. An average crystallite size is determined from the full‐width at half‐maximum of the strongest reflection by using Scherrer's approximation by powder X‐ray diffractometry. The efficiency of CoFe₂O₄@SiO₂@Co (III) salen complex is investigated in the synthesis of spirooxindoles of malononitrile, various isatins with 1,3‐dicarbonyles. The nanocatalyst demonstrated excellent catalytic activity that gave the corresponding coupling products in good to excellent yields. Moreover, the recoverability and reusability of CoFe₂O₄@SiO₂@Co (III) salen complex is investigated where nanocatalyst could be recovered and reused at least five times without any appreciable decrease in activity and selectivity, which confirmed its high efficiency and high stability under the reaction conditions and during recycling stages.     

Mo (CO)6‐assisted Pd‐supported magnetic graphene oxide‐catalyzed carbonylation‐cyclization as an efficient way for the synthesis of 4(3H)‐quinazolinones

In this paper, a novel catalyst is introduced based on the immobilization of palladium on modified magnetic graphene oxide nanoparticles. The catalyst is characterized by several methods, including transmission electron microscopy, scanning electron microscopy, X‐ray fluorescence, vibrating‐sample magnetometer, Fourier transform‐infrared and dynamic light scattering (DLS) analysis. The activity of the catalyst was investigated in the synthesis of 4(3H)‐quinazolinones via Pd‐catalyzed carbonylation‐cyclization of N‐(2‐bromoaryl) benzimidamides by Mo (CO)₆. The Mo (CO)₆ is used as a carbon monoxide source for performing the reaction under mild conditions. The catalyst showed good reusability, and no change in activity was observed after 10 cycles of recovery.     

Oxotitanium(IV) complexes of some bis‐unsymmetric Schiff bases: Synthesis,structural elucidation and biomedical applications

A number of oxotitanium(IV) complexes of the type TiOL with bis‐unsymmetric dibasic tetradentate Schiff base (LH₂) containing ONNO donor atoms have been synthesized. Mono‐Schiff base (OPD‐HNP) was prepared by the condensation of 1:3 molar ratio of 2‐hydroxy‐1‐naphthaldehyde (HNP) with o‐phenylenediamine (OPD). Dibasic unsymmetric tetradentate diamine Schiff bases were prepared by the reaction of OPD‐HNP with 2‐hydroxyacetophenone, 2‐hydroxypropeophenone, benzoylacetone, acetylacetone and ethylacetoacetate. Further, titanylacetylacetonate was reacted with these ligands to obtain their metal complexes. On the basis of analytical and physiochemical data, the formation of complexes as TiOL was suggested having square pyramidal geometry. Quantum mechanical approach also confirmed this geometry. The assessment of the synthesized ligands and their complexes showed that some behave as good inhibitors of mycelial growth against selected phytopathogic fungi but weak inhibitors against some selected bacteria. A few of them also showed antioxidant properties.     

Facile synthesis of inorganic–organic Fe2W18Fe4@NiO@CTS hybrid nanocatalyst induced efficient performance in oxidative desulfurization of real fuel

In this work, a new nanocatalyst, Fe₂W₁₈Fe₄@NiO@CTS, was synthesized by the reaction of sandwich‐type polyoxometalate (Fe₂W₁₈Fe₄), nickel oxide (NiO), and chitosan (CTS) via sol–gel method. The assembled nanocatalyst was systematically characterized by FT‐IR, UV–vis, XRD, SEM, and EDX analysis. The catalytic activity of Fe₂W₁₈Fe₄@NiO@CTS was tested on oxidative desulfurization (ODS) of real gasoline and model fuels. The experimental results revealed that the levels of sulfur content and mercaptan compounds of gasoline were lowered with 97% efficiency. Also, the Fe₂W₁₈Fe₄@NiO@CTS nanocatalyst demonstrated an outstanding catalytic performance for the oxidation of dibenzothiophene (DBT) in the model fuel. The major factors that influence the desulfurization efficiency and the kinetic study of the ODS reactions were fully detailed and discussed. The probable ODS pathway was proposed via the electrophilic mechanism on the basis of the electrophilic characteristic of the metal‐oxo‐peroxo intermediates. The prepared nanocatalyst could be reused for 5 successive runs without any appreciable loss in its catalytic activity. As a result, the current study suggested the potential application of the Fe₂W₁₈Fe₄@NiO@CTS hybrid nanocatalyst as an ideal candidate for removal of sulfur compounds from fuel.     

In situ green synthesis of Cu‐Ni bimetallic nanoparticles supported on reduced graphene oxide as an effective and recyclable catalyst for the synthesis of N‐benzyl‐N‐aryl‐5‐amino‐1H‐tetrazoles

In the present work, for the first time we have designed a novel approach for the synthesis of N‐benzyl‐N‐aryl‐5‐amino‐1H‐tetrazoles using reduced graphene oxide (rGO) decorated with Cu‐Ni bimetallic nanoparticles (NPs). In situ synthesis of Cu/Ni/rGO nanocomposite was performed by a cost efficient, surfactant‐free and environmentally benign method using Crataegus azarolus var. aronia L. leaf extract as a stabilizing and reducing agent. Phytochemicals present in the extract can be used to reduce Cu²⁺ and Ni²⁺ ions and GO to Cu NPs, Ni NPs and rGO, respectively. Analyses by means of FT‐IR, UV–Vis, EDS, TEM, FESEM, XRD and elemental mapping confirmed the Cu/Ni/rGO formation and also FT‐IR, NMR, and mass spectroscopy as well as elemental analysis were used to characterize the tetrazoles. The Cu/Ni/rGO nanocomposite showed the superior catalytic activity for the synthesis of N‐benzyl‐N‐aryl‐5‐amino‐1H‐tetrazoles within a short reaction time and high yields. Furthermore, this protocol eliminates the need to handle HN₃.     

Synthesis and characterization of indium and thallium immobilized on isonicotinamide‐functionalized mesoporous MCM‐41: Two novel and highly active heterogeneous catalysts for selective oxidation of sulfides and thiols to their corresponding sulfoxides and disulfides

Two highly ordered isonicotinamide (INA)‐functionalized mesoporous MCM‐41 materials supporting indium and thallium (MCM‐41‐INA‐In and MCM‐41‐INA‐Tl) have been developed using a covalent grafting method. A surface functionalization method has been applied to prepare Cl‐modified mesoporous MCM‐41 material. Condensation of this Cl‐functionalized MCM‐41 with INA leads to the formation of MCM‐41‐INA. The reaction of MCM‐41‐INA with In(NO₃)₃ or Tl(NO₃)₃ leads to the formation of MCM‐41‐INA‐In and MCM‐41‐INA‐Tl catalysts. The resulting materials were characterized using various techniques. These MCM‐41‐INA‐In and MCM‐41‐INA‐Tl catalysts show excellent catalytic performance in the selective oxidation of sulfides and thiols to their corresponding sulfoxides and disulfides. Finally, it is found that the anchored indium and thallium do not leach out from the surface of the mesoporous catalysts during reaction and the catalysts can be reused for seven repeat reaction runs without considerable loss of catalytic performance.     

Preparation,characterization, and assessment of cytotoxicity,antioxidant, antibacterial,antifungal, and cutaneous wound healing properties of titanium nanoparticles using aqueous extract of Ziziphora clinopodioides Lam leaves

In recent decades, nanotechnology is growing rapidly owing to its widespread application in science and industry. The aim of the experiment was chemical characterization and evaluation of cytotoxicity, antioxidant, antibacterial, antifungal, and cutaneous wound healing activities of titanium nanoparticles using aqueous extract of Ziziphora clinopodioides Lam leaves (TiNPs@Ziziphora). These nanoparticles were characterized by fourier transformed infrared spectroscopy (FT‐IR), field emission scanning electron microscopy (FE‐SEM), energy dispersive X‐ray spectroscopy (EDS), and UV–visible spectroscopy. The synthesized TiNPs@Ziziphora had great cell viability dose‐dependently (Investigating the effect of the plant on human umbilical vein endothelial cells (HUVECs) cell line) and revealed this method was nontoxic. Then, 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) free radical scavenging test was done to assess the antioxidant properties, which indicated similar antioxidant potentials for TiNPs@Ziziphora and butylated hydroxytoluene. Agar diffusion tests were applied to determine the antibacterial and antifungal characteristics. Minimum Inhibitory Concentration (MIC), Minimum Bactericidal Concentration (MBC), and Minimum Fungicidal Concentration (MFC) were specified by macro‐broth dilution assay. The data were analyzed by SPSS 21 software (Duncan post‐hoc test). TiNPs@Ziziphora indicated higher antibacterial and antifungal effects than all standard antibiotics (p ≤ 0.01). Also, TiNPs@Ziziphora inhibited the growth of all bacteria at 2‐16 mg/ml concentrations and removed them at 2‐32 mg/ml concentrations (p ≤ 0.01). In case of antifungal properties of TiNPs@Ziziphora, they prevented the growth of all fungi at 2‐8 mg/ml concentrations and destroyed them at 2‐16 mg/ml concentrations (p ≤ 0.01). In vivo experiment, after creating the cutaneous wound, the rats were randomly divided into six groups: untreated control, treatment with Eucerin basal ointment, treatment with 3% tetracycline ointment, treatment with 0.2% TiO₂ ointment, treatment with 0.2% Z. clinopodioides ointment, and treatment with 0.2% TiNPs@Ziziphora ointment. These groups were treated for 10 days. For histopathological and biochemical analysis of the healing trend, a 3 × 3 cm section was prepared from all dermal thicknesses at day 10. Use of TiNPs@Ziziphora ointment in the treatment groups substantially reduced (p ≤ 0.01) the wound area, total cells, neutrophil, and lymphocyte and remarkably raised (p ≤ 0.01) the wound contracture, hydroxyl proline, hexosamine, hexuronic acid, fibrocyte, and fibrocytes/fibroblast rate compared to other groups. In conclusion, the results revealed the useful non‐cytotoxic, antioxidant, antibacterial, antifungal, and cutaneous wound healing effects of TiNPs@Ziziphora.     

Mixed Ligand Palladium(Ⅱ) Complex with NS-Bidentate S-Allyldithiocarbazate Schiff Base: Synthesis, Spectral Char-acterization, Crystal Structure and Decoding Intermolecular Interactions with Hirshfeld Surface Analysis

A new mixed ligand palladium(II) complex with bidentate NS‐donor chelate, [PdCl(PPh₃)L] (L: S‐allyl β‐N‐(benzylidene)dithiocarbazate), has been prepared and characterized using single crystal X‐ray diffraction and spectroscopic (electronic, IR, ¹H NMR and ¹³C NMR) techniques. The shorter Pd? P bond distance, 2.255(7) Å, than the sum of the single bond radii for palladium and phosphorus (2.41 Å), showed partial double bond character. Visualizing and exploring the crystal structure using Hirshfeld surface analysis showed the presence of π··· π, N··· π, C? H··· π, Cl···H and weak C? H···S interactions as most important intermolecular interactions in the crystal lattice, which are responsible to extension of the supramolecular network of the compound and stabilization of the crystal structure.