Structure and morphological stability of (Lu1–xEux)2O3 thin films

(Lu_1–xEu_x)₂O₃ smooth, crack‐free, transparent films were prepared by the Pechini sol–gel method and a spin‐coating technique. Thermogravimetric analysis, differential thermal analysis and FITR spectroscopy were used to study the chemical processes during annealing of the films. Film structure, morphology and optical properties were investigated. X‐ray diffraction (XRD) analysis reveals the cubic phase of (Lu_1–xEu_x)₂O₃ films annealed in the 600–1000 °C temperature range. Smooth and crack‐free films with thicknesses of 250–1000 nm were obtained in the 600–800 °C temperature range. The thickness upper limit (1000 nm) of morphological stability of films (Lu_1–xEu_x)₂O₃ on sapphire substrates has been studied.     

Octanuclear Palladacycles with B(3)–H Bond Activation of o-Carborane†

Herein, we describe the synthesis of a carborane-supported octanuclear palladacycle complex, Pd₈(o-C₂B₁₀H₁₀CS₂CH₃)₄Cl₄(CH₃CN)₄ (complex 1 ), with B(3)–H activations on o-carborane ligand. The substitution reaction of 1 has been explored, and three of its substituted complexes Pd₈(o-C₂B₁₀H₁₀CS₂CH₃)₄Cl₄(L)₄ (L = ^tBuNC, 2 ; L = C₅H₅N, 3 ; L = C₄H₈S, 4 ) have been synthesized. The m- and p-carborane disubstituted ligands m- and p-C₂B₁₀H₁₀(CS₂CH₃)₂ (ligands 5 and 6 ) as well as their B—H activated carborane complexes [m-C₂B₁₀H₉(CS₂CH₃)₂PdCl] ( 7 ) and [p-C₂B₁₀H₈(CS₂CH₃)₂][PdCl(^tBuNC)]₂ ( 8 ) have also been synthesized by the similar method. All of these complexes have been characterized, including X-ray single crystal diffraction, NMR spectroscopy, IR spectroscopy and elemental analysis methods.      

Paramagnetic behavior of Zn1−xMnxO at room temperature

Mn‐doped ZnO were synthesized by solid state reaction and sol‐gel method respectively. It was found that samples synthesized by solid state reaction containing Mn₂O₃ and MnO₂ are a mixture of ferromagnetic and paramagnetic phases. Contrary, samples without second phases were found to be paramagnetic at room temperature. According to previous report, interface effects between Zn‐rich Mn₂O₃ and MnO₂ interfaces may be the origin of the ferromagnetic behavior observed in our samples prepared by solid reaction, so the alloy of Zn_1−xMn_xO may be paramagnetic at room temperature. Prepared by sol‐gel technique, the samples without second phases in the XRD patterns are also room‐temperature paramagnetic. Therefore we believe that the magnetism of Zn_1−xMn_xO is paramagnetic at room temperature. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Green sol–gel auto-combustion synthesis,characterization and study of cytotoxicity and anticancer activity of ErFeO3/Fe3O4/rGO nanocomposite

Due to the fact that researchers and scientists have been interested in environmentally friendly synthesis using plant extracts because of the wide distribution of plants, their ease of availability, and their safety in use, in the current work, ErFeO₃/Fe₃O₄/rGO nanocomposite was produced using a green chemistry method via sucrose indicating the importance of both an active capping and reducing agent for the synthesis of nanocomposite materials with well-organized biological properties. Number of methods, including TEM, SEM, XRD, BET-BJH, VSM, and HRTEM, were used to characterize the produced nanocomposite. The XRD data showed that the produced nanocomposite had pure particles with a range of 37 ± 2 nm in size, which was validated by TEM examination. Additionally, the nanocomposite's cytotoxicity was examined to test its anti-proliferative effect against the T98, and SH-SY5Y cancer cell lines. It was also discussed how to effectively induce cancer cell death in vitro when manufactured nanocomposite was present. The results showed that the percentage of cells that survived was drastically decreased by the synthesized nanocomposite. However, further research must be done to identify the precise linked mechanisms.     

Synthesis of ceria nanoparticles for the catalytic activity of cyclohexene epoxidation and selective detection of nitrite

Based on a few noteworthy features, cerium oxide nanoparticles have gained significance in nanotechnology. The effective microwave combustion method (MCM) and the conventional sol–gel (CRSGM) technologies are used in this study to successfully generate the crystalline CeO₂ nanoparticles (NPs). Additionally, using a variety of spectroscopic and analytical methods, the synthesized CeO₂ NPs are examined to assess to understand their structure and morphology. The XRD patterns of CeO₂ NPs show that the structure exhibits a face-centered cubic lattice. Then, with demonstrated good conversion and selectivity, the impact of the epoxidation reaction of cyclohexene was examined. Finally, it can be said that using CeO₂ nanoparticles is an efficient strategy to increase the catalytic activity toward the epoxidation reaction of cyclohexene. In the presence of acetonitrile as a solvent and H₂O₂ as an oxidant, the catalyst samples utilized in the cyclohexene epoxidation reaction were examined. In this study, the CeO₂ catalyst outperformed all other catalysts in terms of cyclohexene maximal conversion and selectivity. After six prolonged cycles, the conversion of cyclohexene oxidation using CeO₂ NPs shows reasonable recyclability and conversion efficiency, making it the best catalyst for an industrial production application.Additionally, the upgraded CeO₂ nanoparticle electrode for nitrite detection has a linear concentration range (0.02–1200 M), a low detection limit (0.22 M), and a higher sensitivity (1.735 A M⁻¹ cm⁻²). CeO₂ NPs, on the other hand, have a quick response time, excellent sensitivity, and high selectivity. Additionally, the manufactured electrode is used to find nitrite in various water samples. Finally, it can be said that using CeO₂ NPs is an efficient strategy to increase the catalytic activity toward cyclohexene oxidation and nitrite.     

Visible Light-Induced C-5 Selective C—H Radical Borylation of Imidazo[1,2-a]pyridines with NHC-Boranes

A visible-light-induced C-5 selective C—H borylation of imidazo[1,2-a]pyridines with NHC-BH₃ via Minisci-type radical borylation reaction has been developed for the first time. The present sustainable protocol provides a new family of regioselectively C5-borylated imidazopyridines that would otherwise be difficult to prepare. It is a supplement to site-selective borylation of azines (nitrogen-containing aromatic heterocycles) and the assembly of sp² carbon-boron bond.      

Silica Aerogel: Synthesis,Characterization, Applications,and Recent Advancements

Silica aerogels have drawn considerable attention due to their low density (almost 95% of the total volume is composed of air), hydrophobicity, optical transparency, low conductivity of heat, and large surface to volume ratio. Sol–gel processing is used to prepare aerogels from molecular precursors. To replace the pore fluid with air while retaining the solid network, a supercritical drying process (the most frequent approach) is used. However, recent technologies use atmospheric pressure to allow for liquid removal followed by chemical alteration of the gel's internal layer, which leaves only a silica network with a porous structure filled with air. This study discusses the sol–gel method for preparing silica aerogels and their various drying processes. Furthermore, various areas of applications of silica aerogels, including electronics, construction, aerospace, purification of water and air, sensing, catalyst, biomedical, absorbent, food packing, textile, etc., are also discussed. Lastly, this review provides a perception of the recent scientific progress along with the futuristic development of silica aerogel.     

π-Complexation and C—H hydrogen bonding in the formation of colored cocrystals

The present study evaluates the potential combination of charge-transfer electron-donor–acceptor π–π complexation and C—H hydrogen bonding to form colored cocrystals. The crystal structures of the red 1:1 cocrystals formed from the isomeric pyridines 4- and 3-{2-[4-(dimethylamino)phenyl]ethynyl}pyridine with 1-[2-(3,5-dinitrophenyl)ethynyl]-2,3,5,6-tetrafluorobenzene, both C₁₄H₄F₄N₂O₄·C₁₅H₁₄N₂, are reported. Intermolecular interaction energy calculations confirm that π-stacking interactions dominate the intermolecular interactions within each crystal structure. The close contacts revealed by Hirshfeld surface calculations are predominantly C—H interactions with N, O, and F atoms.