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The Cu⋯Cu interactions, known as cuprophilicity, play a significant role in copper–chalcogenide functional materials. Three dinuclear copper chalcogenone complexes, [(L1CuI)2] (1), [(L2CuI)2] (2) and [Cu2(L3)4]PF6 (3), have been isolated and characterized. L1 = 1-(9-methyl anthracene)-2-isopropyl-benzimidazole-2-thione; L2 = 1-(9-methyl anthracene)-2-isopropyl-benzimidazole-2-selenone and L3 = 1-pyridine-2-isopropyl-imidazole-2-selenone, ligands and 1–3 were characterized by 1H NMR, 13C NMR, FT-IR, and SCXRD. Complexes 1 and 2 compress a four-membered strained ring system bridged by iodine, whereas 3 consists of a similar-four-membered ring core bridged by a selenium ligand. The Cu⋯Cu interactions in the crystal structures are observed (2.591 Å for 1, 2.576 Å for 2, and 2.523 Å for 3). The bridging ligand shows a key contribution to the Cu⋯Cu interactions. The density functional theory calculations also confirm the presence of d10⋯d10 interactions, which are predominantly covalent in nature. The computational study also shows the effect of the bridged ligands on the d10⋯d10 interactions and overall stability of the complexes, where complex 2 is the most stable followed by 1, and after that 3, although the d10⋯d10 interactions were the strongest in the case of 3. [ABSTRACT FROM AUTHOR]

A rigid pentadentate chelating ligand (H2L) has been utilized to synthesize a series of octacoordinate mononuclear complexes, [Dy(L)(Ph3PO)(OOCR)] (where R = C6H5 (1), C(CH3)3 (2), CF3 (3)) and a dinuclear complex, [Dy2(L)2(Ph3PO)2{(OOC)2C6H4}] (4) based on the highly anisotropic Dy(III) ion. All the complexes were structurally characterized by single-crystal X-ray diffraction studies. The complexes were formed by the coordination action of the dianionic pentadentate ligand [L]2−, one phosphine oxide, and carboxylate ligands. DC and AC magnetic measurements were performed on 1–4. Complexes 1–4 show SMM behaviour, under zero DC field for 1 and 4, and under 500 Oe and 1000 Oe DC fields for 2 and 3 respectively, with thermally activated, Raman, and Raman and quantum tunnelling dominant relaxation mechanisms for 1 and 2, 3 and 4, respectively. [ABSTRACT FROM AUTHOR]

This study introduces a novel photo-rechargeable battery featuring a photocathode that comprises TiO2 co-sensitized with copper tetraphenylporphyrin (CuTPP) dye and copper-doped vanadium pentoxide (Cu:V2O5). In an unbiased mode under illumination, this architecture facilitates charging up to 1.4 V, delivering a photocharging capacity of 91 mA h g−1, a feat made possible by Förster Resonance Energy Transfer (FRET) from Cu:V2O5 to CuTPP dye. The energy level mismatch inherent in these materials restricts direct photo-excited charge injection but enables a highly proficient energy transfer, accomplishing a FRET efficiency of 29.2%, attained at a Förster distance of 3.3 nm. This process yields a photocharging capacity of 268 mA h g−1 under 1 sun irradiance, a significant enhancement from 210 mA h g−1 capacity in the dark, both determined at 100 mA g−1. The V2O5 analogue of this photo-battery exhibits a reduced performance owing to lower electrical conductivity and inefficient charge separation. Both V2O5 and Cu:V2O5-based photo-batteries demonstrate respectable overall photoconversion and storage efficiencies, recording 3.9% and 3.3% respectively. The TiO2/CuTPP/Cu:V2O5/Zn2+/Zn flakes-activated carbon/Ni photo-battery shows promising longevity as it maintains ∼100% of its initial capacity in light, indicating a commendable cycling stability. This investigation proposes a paradigm shift for photo-battery development by obviating the necessity for energy-level-aligned photocathodes. [ABSTRACT FROM AUTHOR]

Amidst the challenges posed by climate change, exploring advanced technologies like nanotechnology is crucial for enhancing agricultural productivity and food security. Consequently, this study investigated the impact of nano SiO2 (nSiO2), nano TiO2 (nTiO2) and SiO2/TiO2 nanocomposites (NCs) on 30-day-old Zea mays L. plants and soil health at concentrations of 100 and 200 ppm. Results showed that nSiO2 and nTiO2 at 100 ppm and SiO2/TiO2 NCs at both concentrations, positively influenced plant growth, with the best stimulation observed at 200 ppm of SiO2/TiO2 NCs. Improved plant growth was associated with higher chlorophyll content, photosynthetic rate, transpiration rate, stomatal conductance, rhizospheric N-fixing and phosphate solubilizing bacterial population and plant nutrient uptake. Additionally, treated plants exhibited increased cellulose and starch levels. Malondialdehyde (MDA) content was lower or similar to that of the control, except at 200 ppm of nTiO2-treated shoots. Antioxidant enzyme activities fluctuated, indicating physiological adjustments. Overall, 100 ppm of nTiO2 as well as nSiO2 and 100 and 200 ppm of SiO2/TiO2 NCs improved soil fertility and Z. mays growth, suggesting potential benefits for sustainable agriculture. The findings lay the foundation for more comprehensive investigations into the long-term fate of nanomaterials in soil and their intricate molecular-level interactions with Z. mays. [ABSTRACT FROM AUTHOR]

In the present work, we have explored a series of unsaturated hexa-18-crown-6 (U18C6) ligands towards designing highly anisotropic Dy(III) based single-ion magnets (SIMs) with the general formula [Dy(U18C6)X2]+ (where U18C6 = [C12H12O6] (1), [C12H12S6] (2), [C12H12Se6] (3), [C12H12O4S2] (4), [C12H12O4Se2] (5) and X = F, Cl, Br, I, OtBu and OSiPh3). By analysing the electronic structure, bonding and magnetic properties, we find that the U18C6 ligands prefer stabilising the highly symmetric eight-coordinated hexagonal bipyramidal geometry (HBPY-8), which is the source of the near-Ising type anisotropy in all the [Dy(U18C6)X2]+ complexes. Moreover, the ability of sulfur/selenium substituted U18C6 ligands to stabilize the highly anisotropic HBPY-8 geometry makes them more promising towards engineering the equatorial ligand field compared to substituted saturated 18C6 ligands where the exodentate arrangement of the S lone pairs results in low symmetry. Magnetic relaxation analysis predicts a record barrier height over 2700 K for [Dy(C12H12O6)F2]+ and [Dy(C12H12S6)X2]+ (where X = F, OtBu and OSiPh3) complexes, nearly 23% higher than those of the top performing Dy(III) based SIMs in the literature. [ABSTRACT FROM AUTHOR]

Objectives The purpose of the comparative study was to evaluate the clinical parameters affecting healing after surgical excision of superficial, potentially malignant oral lesions using Platelet Rich Fibrin (PRF) and Collagen Membrane. Material and methods: A total of 100 patients requiring treatment for oral mucosal lesions (OML) were enrolled through a randomized selection of two different groups, where Group 1 (50 patients) received PRF while Group 2 (50 patients) received Collagen membrane following excisional biopsy. Parameters checked were Pain, Clinical Healing, Granulation Tissue, Epithelialization, Wound Contracture, and Complications postoperatively at 3rd, 7th and 30th day. Results: Group 1 showed better results with post-operative pain, clinical healing and granulation presence when compared to Group 2. Conclusion: PRF can be ascertained as a better dressing material than Collagen Membrane with better healing potential.

A cobalt(II) complex and manganese(II) coordination polymer, formulated as [Co2(H2btca)(mbpy)4][H2btca]·4H2O (1) and {Mn2(btca)(mbpy)2(H2O)2}n (2) (H4btca = 1,2,4,5-benzenetetracarboxylic acid; mbpy = 4,4′-dimethyl-2,2′-bipyridyl), constructed by mixed bipyridine-tetracarboxylic ligands were synthesized and characterized. Single-crystal structural analyses reveal that compound 1 is a discrete neutral binuclear molecule, while compound 2 is a two-dimensional (2D) coordination polymer. The metal ions in these compounds are well isolated, with an intramolecular Co2+⋯Co2+ distance of 9.170 Å for 1 and Mn2+⋯Mn2+ separation of 10.984 and 11.164 Å for 2 due to the bulk tetracarboxylic linker. This isolation gives rise to a single-ion magnetism origin of the compounds. Magnetic studies reveal a large zero-field splitting parameter D of 82.6 cm−1 for 1, while a very small D of 0.42 cm−1 was observed for 2. Interestingly, dynamic ac magnetic measurements exhibited slow magnetic relaxation under the external dc field of the two compounds, revealing the field-supported single-ion magnet (SIM) of 1 and 2. The detailed theoretical calculations were further applied to understand the electronic structures, magnetic anisotropy, and relaxation dynamics in 1 and 2. Combined with our recently reported compound (Eur. J. Inorg. Chem., 2022, e202200354), the foregoing results provide not only a rare binuclear cobalt(II) SIM and the first 2D manganese(II) SIM coordination polymer but also a bipyridine-tetracarboxylic ligand approach toward novel SIMs. [ABSTRACT FROM AUTHOR]

Environmental problems can potentially be solved by covalent organic frameworks (COFs) that contain predesigned porous architectures. Herein, we developed an amorphous tetrazine–triazine-functionalized covalent organic framework (TzTPT-COF) by performing one-pot polycondensations of 2,4,6-tris-(4-formylphenoxy)-1,3,5-triazine (TPT-CHO) and s-tetrazine-diamine (Tz). The TzTPT-COF possesses ordered-disordered accessible nano-channels with an experimental pore width of 8.5 nm and simulated pore width of 6.4 nm. We detail the characterization of two-dimensional TzTPT-COF with readily accessible 8.5 nm-sized pores, which was subsequently employed as a porous adsorbent for the static and dynamic adsorption of small dye molecules, especially methylene blue from dye-adulterated water. Additionally, the COF quickly attained up to 99% of its maximum adsorption capacity within 15 min. The thermal stability of the COF was maintained, with the onset of gradual weight loss observed at 280 °C. Furthermore, the COF exhibited no crystallinity and possesses a mesoporous structure. The experimental findings and in silico simulation revealed that to create COF-based adsorbents with effective dye adsorption capabilities, it is necessary to concurrently consider the inherent pore size of the COF material as well as the size of the organic dye molecules. The TzTPT-COF has a great deal of potential as an adsorbent material for eliminating cationic dyes and other organic pollutants from wastewater due to the high adsorption efficiencies, ultrafast kinetics, and outstanding reusability. Hence, the present findings suggest that COFs can also be proven to be highly versatile porous materials for various environmental remediation applications. [ABSTRACT FROM AUTHOR]

Improved graphitic carbon nitride (g‐C3N4) was synthesized through a unique one‐step cost‐effective technique involving a dynamic gas bubbling phenomenon using ammonium chloride (NH4Cl) as a bubbling agent. An extensive investigation was carried out to optimize the weight ratio of NH4Cl and melamine during the thermal pyrolysis process. Here, we report an improved form of g‐C3N4 namely "expanded g‐C3N4" with increased interlayer distance and remarkable volume expansion. The surface area of this improved version has notably increased leading to higher photocatalytic efficiency as compared with its counterpart, an synthesized without adding NH4Cl. Synthesized photocatalyst materials were further used to study the Rhodamine B photodegradation under visible light. It was observed that the expanded g‐C3N4 showed a 2.4 times higher photodegradation rate than its counterpart and degraded 94% of the dye in just 30 min. [ABSTRACT FROM AUTHOR]