A Fe₃O₄@COOH-activated carbon (Fe₃O₄@CFC-COOH) was prepared via carboxyl-functionalization of the activated carbon derived from feather waste, followed by co-precipitation of Fe²⁺ and Fe³⁺ under alkaline conditions. This hybrid organic–inorganic porous compound was applied for the in-situ synthesis of TMU-16 MOF and, subsequently, further engaged as support for immobilizing of Cu nanoparticles. The multi-application of the as-synthesized nanocomposite was investigated in the synthesis of tetrahydrobenzo[b]pyrans derivatives and the removal of methylene blue from aqueous media. The adsorption process fitted well with the Freundlich model and has followed the pseudo-second-order model kinetic model. Also, the Fe₃O₄@CFC-COOH@TMU-16@Cu exhibited high catalytic activity in the synthesis of tetrahydrobenzo[b]pyran derivatives.

A Fe₃O₄@activated carbon-COOH (Fe₃O₄@CFC-COOH) was prepared via carboxyl-functionalization of the activated carbon derived from feather waste, followed by co-precipitation of Fe²⁺ and Fe³⁺ under alkaline conditions. This hybrid organic–inorganic porous compound was applied for in-situ synthesis of TMU-16 metal–organic framework and, subsequently, further engaged as support for immobilizing of Cu nanoparticles. The multi-application of the as-synthesized nanocomposite was investigated in the synthesis of tetrahydrobenzo[b]pyrans derivatives and the removal of methylene blue from aqueous media. The maximum absorption percentage (Re) for the removal of methylene blue was 96%. The adsorption process fitted well with the Freundlich model and has followed the pseudo-second-order kinetic model. Also, the Fe₃O₄@CFC-COOH@TMU-16@Cu exhibited high catalytic activity in the synthesis of tetrahydrobenzo[b]pyran derivatives with a wide range of aldehydes bearing electron-donating and electron-withdrawing groups.

Here, Co-Cu/ZIF@HAp, a novel HAp-based nanocomposite, was synthesized. The prepared nanocomposite performed well as a photocatalyst in the degradation of organic pollutants. From the investigation, it was found that two common organic dyes, namely, Eosin Yellow (EY) and Brilliant Green (BG), were degraded up to 98.3% and 99.5%, respectively within 50 min by as-synthesized photocatalyst. Further, higher stability and reusability of the photocatalyst were ensured by recyclability test.

In this study, a novel hydroxyapatite (HAp)-based composite, Co-Cu/ZIF@HAp, was constructed through in situ growth and simultaneous sonication followed by magnetic string. Herein, the HAp-based nanocomposite was obtained in which HAp was coated with cobalt–copper bimetallic zeolitic imidazolate framework (ZIF) in one-pot synthesis method. The as-synthesized composite was characterized by PXRD, FTIR, FE-SEM, EDS, HR-TEM, TGA-DTG, XPS, BET, and UV-DRS techniques, which suggested that HAp was well coated with bimetallic ZIF. The prepared composite was utilized as a catalyst in degradation of organic pollutants. Removal of organic pollutants such as organic dyes has become indispensable due to their higher stability, toxicity, and mutagenic nature. Two commonly found organic dyes, namely, Eosin Yellow (EY) and Brilliant Green (BG), were chosen for the investigation of photocatalytic activity of the as-prepared catalyst. The degradation process was carried out under solar radiation, and there was no utilization of any oxidizing and reducing agent. Several parameters such as amount of catalyst dose, initial concentration of the dye solution, and effect of different pH conditions were evaluated for better understanding of photocatalytic performance of Co-Cu/ZIF@HAp composite. Both EY and BG dyes were almost degraded up to 98.3% and 99.5%, respectively, within 50 min by the as-prepared nanocomposite. Also, quenching test was performed that confirmed the formation of superoxide radicals (O₂ ^−.) as reactive oxygen species (ROS) in the photodegradation process. The as-synthesized catalyst was repeatedly used for five times to ascertain the stability and reusability of catalyst.

The chemically stable green mixed synthesis of Co₃O₄.NiO.ZrO₂ nanoalloy has a spherical shape with an average particle size of 32 nm. This ferromagnetic nanoalloy with strong saturation magnetization (Ms) (12.42 emu/g) and low coercivity (Hc) (282.36 Oe) can be used in bio-fresh magnetic storage devices, ferrofluids technologies, and magnetically calorie refrigeration. Also, the nanoalloy shows exceptional antibacterial activity against the gram-positive and gram-negative high-pathogenic bacteria.

The tri-metallic magnetic nanoalloy synthesized via the eco-friendly procedure discussed here contains cobalt (Co), nickel (Ni), and zirconium (Zr) metals in a 3:1:1 M ratio (Co₃O₄.NiO.ZrO₂ nanoalloy). Two different plant extracts which are rich in biologically active compounds from Spermacoce hispida and Vernonia cinereum were combined to get a multispecies nanoalloy with magnetic properties and medicinal values. The Fourier transform infrared, X-ray diffraction, and transmission and scanning electron microscopes analyses confirmed the spherical shape of the bioinspired Co₃O₄.NiO.ZrO₂ nanoalloy. The average size of our nanoalloy was 32 nm, but the individual nanoparticles are between 21 and 73 nm in size. A vibrating sample magnetometer study of the magnetic characteristics of the nanoalloy reveals strong saturation magnetization (12.42 emu/g), low retentivity (Mr), and low coercivity (Hc) (282.36 Oe). The higher saturation magnetization in nanoalloy is attributed to their larger particle size, a high degree of crystalline structure, and slight external spinning deformation. The low coercive field (Hc) value reveals the unique soft nature of our nanoalloy. The disc diffusion study confirms that a 6.3 μg/mL solution of the nanoalloy kills almost 96% of the harmful bacteria like Bacillus subtilis (29 mm), Bacillus cereus (26 mm), and Escherichia coli (21 mm). It shows a moderate effect of 85% killing factor against Staphylococcus albus (17 mm), Pseudomonas aeruginosa (13 mm), and Klebsiella pneumoniae (15 mm) bacteria.

A new hydrazone ligand (AlloxHQ) and its copper (II) complexes have been synthesized and characterized. Mono-, bi- and tri-nuclear complexes are obtained. AlloxHQ and its complexes showed antitumor activity toward Ehrlich Ascites Carcinoma and coordination with copper improved the antitumor activity. The biological activity was confirmed by molecular docking study.

Reaction of 1-(4-methylquinoline-2-yl)hydrazine with Alloxan yielded a new hydrazone ligand (AlloxHQ). Binary copper (II) AlloxHQ complexes have been successfully prepared utilizing different copper (II) salts (chloride, bromide, sulfate, and acetate). Moreover, ternary complexes have been prepared by using secondary ligands; 1,10-phenanthroline and oxine. The structures of AlloxHQ and Cu (II)-AlloxHQ complexes have been investigated with the aid of elemental analysis, nuclear magnetic resonance, infrared, electronic, mass, and electron spin resonance spectra, thermal analysis in addition to measurements of molar conductivity and magnetic susceptibility. Mono-, bi-, and tri-nuclear complexes were obtained, reflecting that the coordinating manner of AlloxHQ is extremely influenced by both the nature of the counter anion and the pH of the medium. AlloxHQ acts as a tri-, bi-, or penta-dentate ligand with different modes of bonding. AlloxHQ and its copper (II) complexes exhibited antitumor activity towards Ehrlich Ascites Carcinoma and coordination with copper improved the antitumor activity. The biological activity was confirmed by molecular docking study to investigate how the title compounds bind to the CDK-5 inhibitor-crystal structure of inhibitor EFP with CDK-2 (PDB ID: 3IG7).

Solid complexes (1–4) of Schiff base ((o-tolylimino)methyl)phenol (HL) with manganese(II), cobalt(II), nickel(II), and copper(II) were synthesized in methanol under reflux. Schiff base (HL) was synthesized through condensation reaction of 2-hydroxybenzaldehyde with o-toluidine. Ligand (HL) and synthesized complexes (1–4) were characterized by using different spectroscopic techniques (UV–visible, FTIR, ¹H NMR, mass spectrometry, powder X-ray diffractometer [XRD]), magnetic measurements, and thermal gravimetric analysis. Spectroscopic analysis demonstrated that ligand being bidentate, in all the complexes, coordinates with metals through the N atom of azomethine group and O atom of the hydroxyl group. Molecular ion peaks (m/z) appear in the mass spectra of complexes confirm the proposed stoichiometry. TGA data of complexes 1 and 2 exhibited water molecules coordinated with the central metal ions (Mn²⁺ and Co²⁺). Magnetic Susceptibility analysis of metal complexes proposed octahedral geometry for Mn(II) and Co(II) complexes. Conductivity analysis was in good agreement with non-electrolyte nature of metal complexes. Global reactivity data exhibited that metal(II) complexes are soft as compared to HL. Moreover, frontier molecular orbital (FMO) findings revealed that among the metal complexes, [Mn(L)₂(H₂O)₂] 1 was having large energy gap showing greater stability and less reactivity, while [Ni(L)₂] 3 was found most reactive among all of them. Values of chemical reactivity descriptors obtained denoted that synthesized metal complexes can be proved as efficient biological candidates owing to their reactivity patterns. In vitro antibacterial and antifungal activity of complexes and ligand were evaluated against different strains of bacteria (Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, and Bacillus subtilis) and fungi (Candida albicans, Aspergillus niger, Trichoderma harzianum, and Aspergillus flavus) via disc diffusion method. The bacterial and fungal growth more efficiently inhibited by the use of metal complexes (1–4) than ((o-tolylimino)methyl)phenol (HL).

A three-component reaction of styrenes, indoles, and diaryl diselenides catalyzed by copper chloride under irradiation of blue LED light is disclosed. This protocol provides 26 examples of β-(hetero)arylselenyl indoles in 60%–87% yields. The proposed mechanism involves the activation of diaryl diselenides by coordination with copper chloride, generation of arylselenium cations by heterolysis of activated diaryl diselenides, electrophilic addition of arylselenium cations to styrenes, and then Friedel–Crafts-type alkylation at the 3-position of NH-indoles.

A three-component reaction of olefins, indoles, and diaryl diselenides catalyzed by copper chloride under irradiation of blue LED light is disclosed. Various diaryl diselenides including diheteroaryl diselenides are suitable for this bifunctionalization of olefins. This protocol provides 26 examples of β-(hetero)arylselenyl indoles in 60%–87% yields. The proposed mechanism involves activation of diaryl diselenides by coordination with copper chloride, generation of arylselenium cations by heterolysis of activated diaryl diselenides, electrophilic addition of arylselenium cations to styrenes, and then Friedel–Crafts-type alkylation at the 3-position of NH-indoles.

Two new Cu(II) complexes are prepared and fully characterized. Complexes have a good thermal stability. Complex 4 could be used in the development of the new drugs for the treatment of oxidative stress-caused pathological disorders, whereas both complexes could be used in further investigations as potential therapeutic candidates for the treatment of various types of cancer.

Two azo dye ligands, bearing different substituents (chlorine atom or methoxy group) in the para-position of the phenyl ring, were employed for the synthesis of two Cu(II) chelates. Full structural affirmation of complexes was assessed. X-ray diffraction measurements revealed that the coordination geometry for Cu atoms in both complexes is square-pyramidal with a ligand:metal ratio of 2:1 where dyes behave as monobasic bidentate ligands. Thermogravimetric analyses of the complexes and their starting dyes were performed to study their thermal stabilities and decomposition behavior confirming the thermal stability of both dyes and complexes. Antioxidative activity of the complexes has been assigned and compared with their parent ligands revealing that the presence of the electron–donor, methoxy group, in the phenyl ring, in both dye and complex, is responsible for the activity (IC₅₀ values of 1.54 for the dye and 1.30 mM for the complex). It should be stated that the complexation of the methoxy-substituted dye leads to enhanced antioxidative activity concurrent to a standard antioxidant molecule of ascorbic acid, making this molecule a promising antioxidant agent. Docking study with vascular endothelial growth factor receptor 2 and Aurora kinase A proteins indicate that complexes exhibit higher binding affinities to proteins than the starting ligand dyes. The most promising structure exhibiting the best docking potential toward both proteins is the complex-bearing methoxy group. The presented results represent a promising start for further investigations of these compounds as potential therapeutic candidates for the treatment of various types of cancer.

A novel 2D bimetallic coordination polymer was obtained under solvothermal conditions. The compound contained cooperative Lewis base–acid sites and employed as a heterogeneous catalyst to promote one-pot deacetalization-Knoevenagel reaction of benzaldehyde dimethyl acetal and malononitrile.

Designing multifunctional catalysts for one-pot organic transformations is highly important due to economic and environmental point of views. Synthesis of bifunctional acid–base tandem catalysts has drawn attention owing to the incorporation of antagonistic active sites in a single catalyst. In the current work, a novel coordination polymer, [NaZn(btc)(H₂O)₃].1.5H₂O (1) (1,3,5-benzenetricarboxylic acid [H₃btc]), was prepared by solvothermal method. Single crystal analysis of 1 revealed that the structure is two dimensional and contains the coexisted Lewis acid–base sites. The material was further characterized by powder X-ray diffraction, FT-IR, thermogravimetric analysis, and temperature programed desorption of NH₃ (NH₃-TPD) and CO₂ (CO₂-TPD). Compound 1 was utilized as a heterogeneous catalyst for tandem deacetalization-Knoevenagel reaction of benzaldehyde dimethyl acetal and malononitrile. It exhibited good activity and structural stability during the reaction.

The biologically potent monometallic and heterobimetallic complexes of Ni(II) were synthesized, and all the synthesized complexes were characterized by various spectroscopic techniques like UV, FTIR, Mass, ¹H-NMR, ¹³C-NMR and Powder X-ray diffraction studies. Heterobimetallic complexes showed good antimicrobial activity against a number of pathogenic fungi and bacteria. The complexes of Ni(II) exhibited effective cytotoxicity activity against MCF-7, HeLa and HaCaT cell lines.

The newly designed trinuclear heterobimetallic complexes [Ni(L)₂(M)₂R₄Cl₂] were synthesized by using methanolic solution of mononuclear Ni (II) complex and various organometallic dichlorides (where L = 1,8-diaminaphthalene [C₁₀H₁₀N₂], M = Sn [IV], Si [IV], Ti [IV] and Zr [IV] and R = Ph, Me, C₅H₅, etc.). The synthesized complexes were characterized on the basis of physico-chemical and spectral (FTIR, UV-visible, ¹H-NMR, ¹³C-NMR, ²⁹Si-NMR, ¹¹⁹Sn-NMR, Mass, and PXRD) studies. IR spectroscopy confirmed the coordination of -NH₂ group to the metal centre. PXRD patterns showed the crystalline nature of all the synthesized complexes. Among the synthesized complexes, mononuclear metal complex adopted square planar geometry, while trinuclear heterobimetallic complexes adopted distorted octahedral geometry. This geometry is also supported by DFT calculations. The in vitro antimicrobial effectiveness of these resulting compounds has been scrutinized against a number of bacterial strains (Pseudomonas aeruginosa, Escherichia coli, Bacillus subtilis, and Staphyloccocus aureus) by agar disc diffusion method and fungal strains (Candida albicans, Fusarium oxysporum and Aspergillus niger) by disc diffusion method, and promising results were attained. The in vitro cytotoxicity activity of the synthesized complexes has been scrutinized against human cervical cancer cells (HeLa) and human breast cancer cells (MCF-7) using MTT assay and showed higher cytotoxicity than cis-platin. Furthermore, their non-toxic nature was confirmed when they tested against human normal keratinocyte cells (HaCaT). The results indicated better biological activity of heterobimetallic complexes than their monometallic complex.

The inherent internal porosity of carbon frameworks derived from ZIF-8 offers significant pathways for the efficient migration of Li-ions and provides storage space. The presence of Zn clusters within the porous carbon structures aids in reducing the formation energy, thereby facilitating the growth of Li metal within the internal pores. The overpotential associated with the Li metallization reaction was effectively mitigated due to the low formation energy, ensuring excellent cycling stability by improving reversibility.

The utilization of lithium (Li) metal as an anode has attracted significant attention for high-energy Li batteries. Unfortunately, uncontrollable Li dendrite cannot be avoided during Li plating and stripping. Much intensive research has been conducted to suppress the dendritic growth by confinement of metallic Li in host architectures. Recently, zeolitic imidazolate frameworks (ZIFs) with a porous features have been used to explore a new approach to storing the Li metal with the advantages of their structural and chemical stability, large surface areas, and large pore cavities. Herein, we investigate the storage capability of metallic Li in a porous carbon framework derived from ZIFs as a function of carbonization temperature. Diversities in pore volumes and channels, the degree of crystallinity, the amount of residual zinc (Zn) metal, and the electrical conductivity can all be controlled by temperature. We demonstrate that well-connected pore channels and adequate electrical conductivity secure the Li-ion pathways and that well-distributed Zn clusters in porous carbon trigger the outward growth of metallic Li from inside the frameworks, resulting in a relatively low overpotential and long-lasting cyclability. Our findings can provide practical insight into advanced electrode design for next-generation Li metal batteries.