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Polyaromatic hydrocarbons (PAHs) are priority pollutants due to their mutagenicity, persistence, and proven carcinogenicity. Consequently, we investigated the photooxidative degradation of prototypical toxic PAHs, namely anthracene (ANTH) and phenanthrene (PHEN), and naphthalene (NAPH) utilizing magnetic CrFe2O4 nanoparticles under visible light LED irradiation. The prepared nanoparticles, characterized by P-XRD, IR, and SEM, reveal a cubic (FCC) structure and an average particle size of 25.6 nm. On Ab initio study we employed spin polarized first-principle calculations using the Full-Potential Linearized Augmented Plane-Wave (FLAPW) method with GGA-mBJ potentials implemented in the Wien2k package to investigate the properties of CrFe2O4 spinel compound; the calculations reveal that CrFe2O4 adopts a cubic crystal structure with space group 227 (Fd-3 m), and exhibits semiconductor characteristics in both spin channels, featuring indirect band gaps of 1.12 eV (spin-up) and 0.43 eV (spin-down) at the Γ-L and K-Γ points, respectively. Furthermore, the material demonstrates ferromagnetic behavior, with a spin magnetic moment of 20 µB per unit cell. Optical spectra analysis concurs with band structure calculations, suggesting the suitability of this material for photovoltaic applications. The CrFe2O4 magnetic nanoparticles were synthesized through an eco-friendly approach using Boswellia carteri resin as a natural surfactant in an aqueous medium. Our synthesized materials exhibited excellent photocatalytic performance, leading to a rapid exponential decay of ANTH and PHEN over 3 h under visible LED light. The effect of different radical scavengers revealed the role of the percentage of active species OH, h+, and ˙O2− in the oxidation of selected PAHs. At neutral pH, the photo-degradation of PAHs (200 g L−1) by CrFe2O4 (10 mg) followed first-order kinetics and the Langmuir model (R2: 0.99). Exceptional degradation efficiencies were achieved, with ANTH exhibiting a removal efficiency of 99 %, PHEN of 90 %, and NAPH of 86 %. These results show the effectiveness of the synthesized materials as benign and environmentally friendly magnetic nanoparticles for removing carcinogenic PAHs, offering a sustainable, green, and reusable (n = 7) catalytic system to address this environmental challenge.

There has been a new approach in the development of antibacterials in order to enhance the antibacterial potential. The nanoparticles are tagged on to the surface of other metals or metal oxides and polymers to achieve nanocomposites. These have shown significant antibacterial properties when compared to nanoparticles. In this article we explore the antibacterial potentials of metal-based and metal–polymer-based nanocomposites, various techniques which are involved in the synthesis of the metal–polymer, nanocomposites, mechanisms of action, and their advantages, disadvantages, and applications.

The reaction of [Fe(η5-C5H4CH2OH)2] (1) with 2 equiv of ClC(O)R (2) (a, R = C6H5; b, R = 2-CH3-C6H4; c, R = 3-CH3-C6H4, d, R = 4-CH3-C6H4) produced the corresponding ferrocenyl carboxylates [Fe(η5-C5H4CH2OC(O)R)2] (3a–d). Treatment of [FcCH2OLi] (4-Li) (Fc = Fe(η5-C5H5)(η5-C5H4)) with (ClC(O))2C6H4 (5) (a, 1,2-((ClC(O))2-C6H4; b, 1,3-((ClC(O))2-C6H4; c, 1,4-((ClC(O))2-C6H4) in a 2:1 M ratio gave (FcCH2OC(O))2-C6H4 (6a–c), while with 1,3,5-(ClC(O))3-C6H3 (7) in a 3:1 M ratio produced 1,3,5-(FcCH2OC(O))3-C6H3 (8). All compounds were characterized by NMR (1H, 13C{1H}) and IR spectroscopy, ESI-TOF mass spectrometry and elemental analysis. The molecular structures of 3a–d and 6b in the solid state were determined by single crystal X-ray structure analysis, showing anti-periplanar orientations of the 1,1′-positioned substituents at ferrocene (3a–d). In the cyclic voltammograms of 3a–d, 6a–d and 8 reversible electrochemical redox processes (Fc/Fc+) were observed, ranging between 146 and 164 mV for 3a–d, ca. 100 mV for 6a–d and at 113 mV for 8 using [NnBu4][B(C6F5)4] as the supporting electrolyte. The molecular electronic structure of 3, 6 and 8 was calculated by DFT methods in order to obtain the HOMO and LUMO absolute and relative energies in addition to electron density and distribution within the molecular arrangements. It was found that different degrees of HOMO-LUMO energy gaps within the series, due to a lowering in the LUMO energy depending on the positions of the carboxylic ester substituents on the aryl rings, are in agreement with the electrochemical results obtained. Keywords: Ferrocenylmethyl, Mono-dicarboxy benzene, Trimesic acid, Solid state structure, Electrochemistry, DFT

Treatment of 3,4-(ClC(O))2-cC4H2S (1) with [FcCH2OLi] (2-Li) (Fc = Fe(η5-C5H5)(η5-C5H4)) in a 1:2 ratio gave 3,4-(FcCH2OC(O))2-cC4H2S (3). Compound 3 decomposes in solution during crystallization to produce FcCH2OH (2) along with 3,4-thiophenedicarboxylic anhydride (4). The cyclic voltammogram of 3 exhibits a reversible ferrocene-related redox couple (E1/2 = 108 mV, vs. Cp2Fe/Cp2Fe+) using [NnBu4] [B(C6F5)4] as the supporting electrolyte. DFT calculations reveal that the energy values of the LUMO orbitals of 3 (3,4-thiophene core) show 1 eV higher energies than that one of 2,5-(FcCH2OC(O))2-cC4H2S (5), both compounds’ HOMO orbitals are close to each other. Compound 4 was characterized by single X-ray structure analysis. It forms a band-type structure based on intermolecular O1···S1 interactions being parallel to (110) and (1–10) in the solid state, while electrostatic C···O interactions between the C=O functionalities of adjacent molecules connect both 3D-networks. Hirshfeld surface analysis was used to gain more insight into the intermolecular interactions in 4, the enrichment ratios (E) suggest that O···H, S···S, and O···C are the most favored intermolecular interactions, as shown by E values above 1.20. The relevance of the weak O···H, O···O, and O···C contacts in stabilizing the molecular structure of 4 was highlighted by the interaction energies between molecular pairs.

Here, we report a visible light-induced-trimetallic catalyst (Cu0.5Zn0.5Fe2O4) prepared through green synthesis using Tilia plant extract. These nanomaterials were characterized for structural and morphological studies using powder x-ray diffraction (P-XRD), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). The spinel crystalline material was ~34 nm. In benign reaction conditions, the prepared photocatalyst oxidized various benzylic alcohols with excellent yield and selectivity toward aldehyde with 99% and 98%; respectively. Aromatic and aliphatic alcohols (such as furfuryl alcohol and 1-octanol) were photo-catalytically oxidized using Cu0.5Zn0.5Fe2O4, LED light, H2O2 as oxidant, 2 h reaction time and ambient temperature. The advantages of the catalyst were found in terms of reduced catalyst loading, activating catalyst using visible light in mild conditions, high conversion of the starting material and the recyclability up to 5 times without loss of the selectivity. Thus, our study offers a potential pathway for the photocatalytic nanomaterial, which will contribute to the advancement of photocatalysis studies.

Here, we report on a phyto-mediated bimetallic (NiFe2O4) preparation using a Boswellia carterii extract, which was characterized by XRD, FT-IR, TGA, electron microscopy, magnetic spectroscopy, and Mössbauer spectroscopy measurements. The prepared nano-catalysts were tested for oxidation of lignin monomer molecules—vanillyl alcohol and cinnamyl alcohol. In comparison with previously reported methods, the nano NiFe2O4 catalysts showed high photocatalytic activity and selectivity, under visible light irradiation with a nitroxy radical initiator (2,2,6,6-tetramethylpiperidinyloxy or 2,2,6,6-tetramethylpiperidine 1-oxyl; TEMPO) at room temperature and aerobic conditions. The multifold advantages of the catalyst both in terms of reduced catalyst loading and ambient temperature conditions were manifested by higher conversion of the starting material.

Here, we report a visible light-induced-trimetallic catalyst (Cu0.5Zn0.5Fe2O4) prepared through green synthesis using Tilia plant extract. These nanomaterials were characterized for structural and morphological studies using powder x-ray diffraction (P-XRD), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). The spinel crystalline material was ~34 nm. In benign reaction conditions, the prepared photocatalyst oxidized various benzylic alcohols with excellent yield and selectivity toward aldehyde with 99% and 98%; respectively. Aromatic and aliphatic alcohols (such as furfuryl alcohol and 1-octanol) were photo-catalytically oxidized using Cu0.5Zn0.5Fe2O4, LED light, H2O2 as oxidant, 2 h reaction time and ambient temperature. The advantages of the catalyst were found in terms of reduced catalyst loading, activating catalyst using visible light in mild conditions, high conversion of the starting material and the recyclability up to 5 times without loss of the selectivity. Thus, our study offers a potential pathway for the photocatalytic nanomaterial, which will contribute to the advancement of photocatalysis studies. [ABSTRACT FROM AUTHOR]

Here, we report on a phyto-mediated bimetallic (NiFe2O4) preparation using a Boswellia carterii extract, which was characterized by XRD, FT-IR, TGA, electron microscopy, magnetic spectroscopy, and Mössbauer spectroscopy measurements. The prepared nano-catalysts were tested for oxidation of lignin monomer molecules—vanillyl alcohol and cinnamyl alcohol. In comparison with previously reported methods, the nano NiFe2O4 catalysts showed high photocatalytic activity and selectivity, under visible light irradiation with a nitroxy radical initiator (2,2,6,6-tetramethylpiperidinyloxy or 2,2,6,6-tetramethylpiperidine 1-oxyl; TEMPO) at room temperature and aerobic conditions. The multifold advantages of the catalyst both in terms of reduced catalyst loading and ambient temperature conditions were manifested by higher conversion of the starting material. [ABSTRACT FROM AUTHOR]