Efficient adsorption‐photocatalysis activity of ternary ZnO‐Sm2O3‐MgO co‐modified biochar for dye removal

Efficient adsorption-photocatalysis activity of ternary ZnO-Sm2O3-MgO co-modified biochar for dye removal

Biochar was modified with ternary metal oxides ZnO, Sm2O3, and MgO via the one-step pyrolysis method. The removal efficiency of 2b-ZnSm/Mg-biochar was 99.46% for 410-mg g−1 RhB solution. Second-order and Langmuir models well described the adsorption kinetics of ZnSm/Mg-biochar.


To boost the adsorption-photocatalytic performances of biochar in wastewater treatment, biochar was modified with ternary metal oxides ZnO, Sm2O3, and MgO (ZnSm/Mg-biochar) via the one-step pyrolysis method. The optimal 2b-ZnSm/Mg-biochar with a Zn/Sm molar ratio of 1:1 exhibited the better removal activity of RhB in comparison with biochar, 2-Mg/biochar, and b-ZnSm/biochar. The removal efficiency and adsorption capacity of 2b-ZnSm/Mg-biochar was 99.46% and 979.22 mg g−1 for RhB solution of 410 mg g−1, respectively. The adsorption kinetics and isotherms of ZnSm/Mg-biochar composites were as described by second-order and Langmuir models, respectively. The abundant vacant sites at the junction interface of ZnO, Sm2O3, MgO, and biochar were favorable for the adsorption and photon capturing, achieving the efficient photo-conversion of RhB under the stimulated solar-light irradiation.

A new Schiff‐base complex of palladium nanoparticles on modified boehmite with di(pyridin‐2‐yl)methanone as a robust, reusable, and selective nanocatalyst in the C‐C coupling reaction

A new Schiff-base complex of palladium nanoparticles on modified boehmite with di(pyridin-2-yl)methanone as a robust, reusable, and selective nanocatalyst in the C-C coupling reaction

Boehmite (AlOOH) is a stable phases of alumina, which was prepared by addition NaOH solutions to Al(NO3)3.9H2O solution, and further, its surface was modified with (3-aminopropyl)triethoxysilane. Then, di(pyridin-2-yl)methanone was immobilized on the surface of modified AlOOH as a heterogeneous Schiff-base ligand. In the final step, a palladium complex was stabilized on its surface (Pd-di(PM)@AlOOH) as a reusable, practical, and novel catalyst in the C-C coupling of Suzuki reaction. This catalyst was characterized by TGA, FT-IR, TEM, SEM, EDS, WDX, and ICP techniques. Due to recoverability and heterogeneous nature of this catalyst, it can be reused for several runs without palladium leaching or any reactivation.


Boehmite is one of the stable phases of alumina that is easily available, and it also has a variety of applications. Therefore in this work, for preparation of AlOOH, Sodium hydroxide (NaOH) solutions was added to aluminum nitrate nonahydrate (Al(NO3)3.9H2O) solution. Then, the surface of AlOOH was modified with (3-aminopropyl)triethoxysilane (APTES), due to high condensation of hydroxyl groups on its surface. Then, di(pyridin-2-yl)methanone (di(PM)) was immobilized on the surface of modified AlOOH toward synthesis of immobilized Schiff-base on AlOOH (di(PM)@AlOOH) as a heterogeneous Schiff-base ligand. Finally, a palladium complex was immobilized on its surface (Pd-di(PM)@AlOOH) as a reusable, practical, and novel nanocatalyst. Pd-di(PM)@AlOOH was characterized by thermogravimetric analysis (TGA) analysis, Fourier-transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), scanning electron microscope (SEM) imaging, energy-dispersive X-ray spectroscopy (EDS) analysis, wavelength-dispersive X-ray spectroscopy (WDX) analysis, and inductively coupled plasma (ICP) analysis. After the characterization of Pd-di(PM)@AlOOH, its performance was used as a highly practical, stable, retrievable, and hybrid organic–inorganic catalyst in the C-C coupling of the Suzuki reaction. The hot filtration study of Pd-di(PM)@AlOOH revealed that it acts heterogeneously in the Suzuki reaction. We found that this catalyst can be recycled for five runs without palladium leaching, as studied by hot filtration test and ICP analysis.

Yolk–shell Ni–Co bimetallic nitride/oxide heterostructures as high‐performance electrode of all‐solid‐state supercapacitor

Yolk–shell Ni–Co bimetallic nitride/oxide heterostructures as high-performance electrode of all-solid-state supercapacitor

Yolk–shell Ni–Co bimetallic nitride/oxide (NiCoNO) heterostructures, derived from NiCo-glycerate solid spheres, demonstrates excellent electrochemical performance as supercapacitor electrode.


Hierarchical core–shell structure is benefit for the fast diffusion and bulk storage of electron/ion while metal nitrides (MN) exhibit metal-like behavior with excellent conductivity. Herein, nickel cobalt glycerate solid spheres (NiCo-G) and nickel cobalt glycerate yolk–shell structure (NiCo-GYS) were successfully synthesized via solvothermal reactions, accompanied by annealing using urea as a cheap and convenient nitrogen source to obtain metal nitride/bimetallic oxide core–shell heterostructure (NiCoNO). Excellent specific capacitance of 1878 F g−1 at 1 A g−1 is displayed by the prepared NiCoNO. Amazingly, the distinct core–shell construction guarantees high stability during the charge/discharge operation. NiCoNO maintains an 83.9% specific capacitance after 5000 cycles at 10 A g−1. Furthermore, the all-solid-state hybrid supercapacitor was assembled using NiCoNO cathode and active carbon (AC) anode components. The device has an excellent capacitive retention rate of 81.1% after 5000 cycles at 10 A g−1 and a good energy density of 64.2 Wh kg−1 at a power density of 900 Wh kg−1. A light-emitting diode (LED) bulb can be lighted for 3 min, indicating the promising practical application prospect of the supercapacitor.

Synergistic modulation of oxygen vacancies and heterojunction structure in Pd@CN@TiO2 promotes efficient photocatalytic Suzuki–Miyaura CC coupling reactions

Synergistic modulation of oxygen vacancies and heterojunction structure in Pd@CN@TiO2 promotes efficient photocatalytic Suzuki–Miyaura C<span class='icomoon'></span>C coupling reactions

In this article, a strategy for the preparation of the Pd@CN@TiO2 composite photocatalyst with the co-regulation of oxygen vacancies and heterojunction structure were developed. The catalyst exhibited excellent catalytic activity in the photocatalytic Suzuki coupling reaction (30 W LED: 455 nm, r.t, 3 h, Yield = 99%).


This paper reports a concise strategy for the controlled preparation of Pd@g-C3N4/TiO2 photocatalysts rich in oxygen vacancies. The scheme forms black TiO2 with oxygen vacancies on a carbon nitride material by in-situ growth and heat treatment, and then utilizes solvothermal reduction to load metallic palladium into the material. The composites were structurally analyzed using Fourier transform infrared (FT-IR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction analysis (XRD), transmission electron microscopy (TEM), electron paramagnetic resonance (EPR), scanning electron microscopy (SEM), elemental mapping, diffuse reflectance spectroscopy (DRS), and inductively coupled plasma (ICP) analysis. The results show that the oxygen vacancies in the black TiO2 materials prepared by the method reported in this paper can effectively improve the separation efficiency of the photogenerated electron–hole pairs and prolong the lifetime of the charge carriers by inhibiting charge recombination. In addition, the heterojunction structure formed between TiO2 and g-C3N4 materials also enhances the photocatalytic performance of the materials to some extent. After a simple optimization of the conditions, the Pd@g-C3N4/TiO2 photocatalyst could promote the Suzuki–Miyaura CC coupling reactions under mild conditions (room temperature, 30 W LED lamp, λ = 455 nm), and good biaryl yields were obtained (optimum yield = 99%). It is very noteworthy that the photogenerated electrons and holes generated by the photoexcited catalyst were confirmed to be the main active species in the photocatalytic process of the catalyst by radical trapping assay and EPR test. The Pd@g-C3N4/TiO2 material reported in this paper has excellent photocatalytic activity and stability in use, which provides a new reference scheme for wider green synthesis and catalysis.

Spectroscopic and electrochemical characterizations of copper complexes with thionine, azure C and azure A

Spectroscopic and electrochemical characterizations of copper complexes with thionine, azure C and azure A

Metal complexes of thionine, azure C and azure A with copper(II) chloride were prepared using two easy steps as dissolving and then slow evaporation in acetonitrile. Cl anion in the chloride salt of PTZ dyes was formed [CuCl3] with CuCl2 in the solvent environment, producing its own ionic character (PTZ+[CuCl3]). ThCu, ACCu and AACu complexes were characterized with theoretical computations, thermal, spectral, electrochemical and fluorescence techniques. Such PTZ+[Metal Sult] complexes can be useful for the applications in optoelectronics with their interesting ionic characters.


Structures held together by secondary interactions such as intramolecular or intermolecular hydrogen bonding, electrostatic and π–π interaction without covalent bonds can exhibit new properties such as high orientation, optoelectronics, biocompatibility and reversibility (self-renewal). Recently, interest has been growing surrounding novel molecules fashioned through non-covalent interactions. These molecules have garnered attention due to their significant roles in both physical and chemical applications. However, the formation of complexes between cationic phenothiazine derivative dyes, commonly employed in electrochemical studies, and diverse metal groups presents a challenge. Therefore, the existing literature contains only a scant number of studies concerning the formation of phenothiazine complexes with metal salts. In this study, metal complexes of thionine, azure C and azure A with copper(II) chloride were prepared using two steps: dissolving and then slow evaporation of dyes-copper(II) chloride in acetonitrile. Besides the theoretical computations, thermal, spectral, electrochemical and fluorescence techniques were performed to determine the characteristics of the monoclinic crystals of Cu–dyes complexes. Cl ion in the dyes and copper(II) chloride conjugated to form [CuCl3], then this anion electrostatically bound to cationic phenothiazine ring bond to be phenothiazine+[CuCl3]. Cu–dye complexes showed interestingly high electron transportation. In addition, prepared Cu–dye complexes have a great potential to be used in optical and spectral applications with extraordinary behaviour of their spectral and fluorescence features.

Palladium(II)‐Imidoyl Complexes: A New Piece in the Puzzle of Organopalladium Anticancer Agents

Palladium(II)-Imidoyl Complexes: A New Piece in the Puzzle of Organopalladium Anticancer Agents

Palladium(II)-Imidoyl Complexes: A New Piece in the Puzzle of Organopalladium Anticancer Agents. The library of organopalladium compounds with anticancer properties was expanded. The new class of Pd-imidoyl complexes bearing PTA, DAPTA and dppf phosphines showed promising results against ovarian cancer in terms of selectivity and apoptosis induction.


Abstract

Our search of new organopalladium compounds able to promote an effective antiproliferative action towards ovarian cancer cells continues. In this paper we have examined for the first time the anticancer activity of palladium imidoyl complexes, for which two different types of phosphines have been chosen as ancillary ligands: i) PTA and DAPTA to take advantage from their solubility in aqueous environment, and ii) dppf for combining the action of the Pd-imidoyl fragment with that, well-known, of ferrocene. The synthetic protocols as well as the exhaustive characterisation of the complexes through spectroscopic and diffractometric methods are described. In vitro tests carried out to assess the cytotoxicity of the new compounds towards two ovarian cancer cell lines (one cisplatin sensitive and the other cisplatin resistant) have revealed an interesting effect of the halide coordinated to the palladium centre (halogen effect). Moreover, all complexes have shown the same activity against the cisplatin-sensitive (A2780) and cisplatin-resistant (A2780cis) cell lines, suggesting a different mode of action with respect to the “classical” platinum-based drugs. Finally, a selection of the most active compounds has shown an interesting selectivity towards ovarian cancer cells.

Hafnium coordination vitrimer based on carboxylate exchange: synthesis, properties, and mechanistic investigations on the [Hf6O4(OH)4(O2CMe)12]2 model compound

Hafnium coordination vitrimer based on carboxylate exchange: synthesis, properties, and mechanistic investigations on the [Hf6O4(OH)4(O2CMe)12]2 model compound

The contribution reports the first hafnium-based coordination adaptable network (Hf−CooAn-10), based on carboxylate/carboxylic acid exchange, and kinetico-mechanistic studies of the exchange in the molecular [Hf6O4(OH)4(O2CMe)12]2/MeCOOH model system, which demonstrates the operationally associative exchange and qualifies the material as a coordination vitrimer.


Abstract

A hafnium-based coordination vitrimer (Hf−CooAN-10) has been prepared by carboxylate ligand exchange from [Hf6O4(OH)4(O2CMe)12]2 and poly-((ethylhexyl methacylate)-co-(carboxyethyl acrylate)) (Mn = 14.4 kg mol−1, Đ = 2.2, 90 : 10 comonomer molar ratio), using a 10 % molar Hf loading with respect to the polymer maximum crosslinking capacity. The material shows high insoluble fraction and expected properties for a 3D network and has been reshaped three times at 50 °C under a 3-ton pressure without significant property alteration. The Hf−CooAN-10 thermomechanical and rheological properties are very similar to those previously reported for the analogous Zr−CooAN-10. The associative nature of carboxylate exchange between the [Hf6O4(OH)4(O2CR)12] crosslinks and the polymer matrix free −COOH functions is suggested by parallel 1H NMR line-broadening kinetic investigations of acetate exchange in the [Hf6O4(OH)4(O2CMe)12]2 precursor with free MeCOOH, the rate of which has a zero-order dependence on [MeCOOH], and by DFT calculations on a [Hf(μ-O2CMe)(O2CMe)2(OH)(H2O)]2 model. The results of these investigations, including the activation parameters for the exchange of both chelating and bridging ligands, are very similar to those of the previously investigated zirconium system and suggest partial acetate dissociation assisted by H-bond formation with a (μ3-OH) ligand as the rate-determining step, followed by acid coordination and intramolecular proton transfer.

Front Cover: Investigations into the AuI and PtII Coordination Chemistry of Bidentate “cis‐Spanning” Ligands (Eur. J. Inorg. Chem. 8/2024)

Front Cover: Investigations into the AuI and PtII Coordination Chemistry of Bidentate “cis-Spanning” Ligands (Eur. J. Inorg. Chem. 8/2024)

The Front Cover shows the almost magical site-selective coordination of AuCl and [Pt(CNC)] to the novel long-range “cis-spanning” ligand LPP in a one-pot reaction, followed by metal−metal bond-formation through chloride abstraction. LPP is easily obtained in a one-pot process by double-deprotonation of phenyl acetylene followed by the addition of chlorodiphenylphosphine. The coordination of the gold and the platinum complexes to the phenylic and to the alkinylic phosphine sites of LPP is highly selective, but a metal−metal interaction is not realized immediately. Subsequent chloride abstraction, however, gives rise to the selective formation of a metal−metal bond. Even mythical creatures might be attracted by these elegant processes. More information can be found in the Research Article by B. Butschke and co-workers.


Investigations into the AuI and PtII Coordination Chemistry of Bidentate “cis‐Spanning” Ligands

Investigations into the AuI and PtII Coordination Chemistry of Bidentate “cis-Spanning” Ligands

The novel long-range “cis-spanning” PP ligand LPP coordinates AuCl and Pt(CNC) in a highly selective manner. Subsequent halide abstraction gives rise to the formation of a Au−Pt bond. While the “cis-spanning” PN ligand LPN does not allow for the generation of heterodinuclear complexes with a metal–metal bond, its potential to serve as a ditopic ligand has been shown in the present work.


Abstract

The novel bidentate PP and PN ligands o-(Ph2P)−C6H4−C≡C−PPh2 (LPP) and o-(Ph2P)−C6H4−4−(C5H9N−Me) (LPN), respectively, have been designed as long-range “cis-spanning“ ligands for the stabilization of heterodinuclear complexes containing two metal atoms in close proximity. The synthesis of heterodinuclear, formal AuIPtII complexes with the ligand LPP is straightforward. In the course of a one-pot reaction, a surprisingly high selectivity for the coordination of AuCl and Pt(CNC) (CNC=2,6-diphenylpyridine-o,o’-diate) to the phenyl-bound and the alkyne-bound PPh2 sites of LPP is observed, respectively. Chloride abstraction from the resulting heterodinuclear complex [(ClAu)(o-Ph2P)−C6H4−C≡C−PPh2(Pt{CNC})] with Ag[SbF6] causes metal–metal bond formation and the generation of the cationic complex [LPPAuPt(CNC)][SbF6]. The high site selectivity for the coordination of the two metals to LPP was investigated by stoichiometric reactions of the ligand with one equivalent of the corresponding precursors. While analogous complexation experiments with LPN have not been successful, the synthesis of the heterodinuclear complex [(ClAu)(o-Ph2P)−C6H4−4-(C5H9N−Me)(PtCl2{dmso})] and of [LPN(AuCl)2] confirm the ability of LPN to serve as a ditopic ligand. In this context, it is noteworthy that [LPN(AuCl)2] constitutes the first amine–AuCl complex featuring a tertiary amine.

Three novel mononuclear 4‐vinylpyridine‐based Fe(III) complexes displaying various spin‐crossover behaviour

Three novel mononuclear 4-vinylpyridine-based Fe(III) complexes displaying various spin-crossover behaviour

Three novel mononuclear Fe(III) complexes based on 4-vinylpyridine coordinated with bis(salicylicdeneaminopropyl)amine and its derivatives exhibited different one-step spin crossover behaviour due to the chemical modification of the pentadentate Schiff base ligands.


Abstract

Three novel mononuclear 4-vinylpyridine-based Fe(III) complexes [FeL(4-VP)]BPh4 (4-VP=4-vinylpyridine; H2L=bis(salicylicdeneaminopropyl)amine, H2salten, 1; H2L=bis(salicylicdeneaminopropyl)methylamine, H2saltenMe, 2; H2L=bis(3-methoxysalicylideneaminopropyl)methylamine, 3-OMeH2saltenMe, 3) were synthesized and characterized. Single-crystal X-ray diffraction analyses revealed that 13 both present the mononuclear structure based on 4-VP coordinated with bis(salicylicdeneaminopropyl)amine and its derivatives, which give 2D architectures by various interactions among cations and counter-ions. Magnetic studies showed that both 1 and 2 exhibit one-step complete spin-crossover (SCO) behaviours with critical transition temperatures (T 1/2) of 178 and 87 K respectively, while 3 exhibits one-step incomplete spin crossover behaviour (T 1/2,3=93 K). The introduction of methyl groups on the amine nitrogen of the Schiff base ligands in 2 and 3 give the bigger repulsive effect, further decrease the cooperation of spin centres, resulting in their spin transition occurring at lower temperatures. In addition, the presence of C−H⋯O weak interactions in 1 and 3 with synergistic effect, led to their spin transition temperatures being higher than that of 2.