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This study presents the rational synthesis of Cu-supported doped-CeO2 catalysts designed for the oxidation of benzylamine, both in the absence and presence of 1,2-diaminobenzene. The catalysts were prepared using a two-step method and characterized by various techniques, including XRD, Raman spectroscopy, BET surface area analysis, NH3-TPD, pyridine-FTIR, H2-TPR, XPS, SEM, and TEM. Raman and XPS analyses confirmed the presence of oxygen vacancy sites, with CuO/CeO2-ZrO2 displaying the highest concentration of these sites. H2-TPR revealed strong metal-support interactions, while NH3-TPD indicated that CuO/CeO2-ZrO2 possessed the greatest number of acidic sites. The pyridine-FTIR results indicates both the acidic sites present on the catalyst surface. The Cu/CeZr sample exhibits the lowest Iu////ITotal ratio (0.0567) compared to the Cu/Ce (0.0843) and Cu/CeSi (0.0672) samples, indicating a higher number of Ce3+ species or a greater number of oxygen defect sites in the sample. The catalyst demonstrated excellent performance in converting benzylamine to imines and was also highly effective in the synthesis of benzimidazole from benzylamine and 1,2-diaminobenzene, broadening its application potential. The superior catalytic activity is attributed to the abundant oxygen vacancies, redox properties, strong metal-support interactions, and acidic sites. Furthermore, the CuO/CeO2-ZrO2 catalyst maintained its efficiency over five consecutive cycles, exhibiting robustness, high functional group tolerance, and reduced reaction times, making it a promising system for diverse catalytic applications. [ABSTRACT FROM AUTHOR]

Novel lignocellulosic biomass‐based fertilizers are developed to enhance crop yields while minimizing ecological impacts. These fertilizers, enriched with macro and micronutrients, feature slow‐release properties, reducing nutrient loss compared to conventional fertilizers. The study emphasizes their potential in sustainable agriculture, offering a viable alternative for soil fertility and crop yield. [ABSTRACT FROM AUTHOR]

In this work, a series of β-Cyclodextrin coated MoO3-Fe2O3 nanocomposites were synthesized by the sol-gel technique for degradation of methylene blue in presence of light from aqueous solutions. The prepared materials were analyzed by using powder XRD, FT-IR, UV-DRS, FE-SEM, HR-TEM, RAMAN, BET, and XPS techniques. The X-ray diffraction spectra of β-CD coated MoO3-doped Fe2O3 confirms the orthorhombic phase of the Fe2(MoO4)3 nanocomposite. The allowed indirect transition optical energy band gap of nanocomposites lies between 2.67 and 1.71 eV. The FE-SEM study revealed that nanoflakes change in the morphology of the nanocomposites sample, and it gives an estimated size below 30 nm. The 10 mgL−1 methylene dye degrades efficiently around 91.62% within 1 h. with reaction condition of 15 mg 5% β-Cyclodextrin coated MoO3-Fe2O3 catalyst, 6 pH, 10 mM concentration of H2O2, at room temperature under sunlight. The pure MoO3 and Fe2O3 gives 38.21% and 77.10%, shows less activity compare with 5βMF catalyst. This study provides newer catalytic system which shows better photocatalytic degradation of dyes from industrial waste water. Highlight: The β-Cyclodextrin coated MoO3-Fe2O3 nanocomposites was successfully prepared by using the cost effective sol-gel technique. The efficiency of nanocomposites was improve using β-Cyclodextrin which gives more active sites and fast charge carrier separation. The reaction successfully carried outstanding efficiency of 5βMF for the degradation of methylene blue. Its result gives 91.62% degradation of MB in short reaction time as compare to the other nanocomposites samples. It concludes that, efficiency of photocatalyst increases with the loading of MoO3 on Fe2O3. This 5βMF catalyst shows better activities within short duration, use of less quantity of catalyst and in works in visible light region. [ABSTRACT FROM AUTHOR]

This study explores a rational synthesis of a molybdenum‐promoted Ce−Si mixed oxide catalyst (MoO3/CeO2−SiO2) to regulate synergies between MoO3 and SiO2 dopant on CeO2, achieving high selectivity in solvent‐free catalytic oxidative coupling of amines to imines using molecular O2 as the oxidant. Comparative efficiency tests were conducted with bare CeO2, CeO2−SiO2, and MoO3/CeO2 catalysts. Characterization techniques, including XRD, Raman spectroscopy, N2‐adsorption‐desorption analysis, FTIR, NH3−TPD, TEM, and XPS, were employed to assess textural properties, acidic features, promoter and dopant dispersion in CeO2 lattice, and oxygen defects. Mo/Ce−Si catalyst exhibited superior acidic sites and a higher concentration of Ce3+ ions (Iu/ITotal), indicating increased oxygen vacancies. This catalyst demonstrated exceptional performance in the oxidative coupling of benzylamine, providing higher conversion and selectivity to the corresponding imine. Remarkably, the Mo/Ce−Si catalyst maintained consistent performance over five recycling runs. The catalyst also proved effective for the selective oxidative coupling of various amine substrates with diverse steric and electronic properties. Experimental results confirmed a plausible reaction mechanism within the concise catalyst design. [ABSTRACT FROM AUTHOR]

Iron oxide and its carbon‐containing biochar have shown efficiencies in Fenton oxidation reactions in recent years. Though magnetic biochar composites have been reported, developing facile, environment‐friendly methods with appropriate activity remains challenging. Removing dye traces from aqueous solutions is a prime concern under water scarcity issues at different levels. We developed a catalyst of biochar with magnetite for dye remediation. Magnetite is homogeneously loaded on biochar surfaces to form Fe3O4‐biochar to efficiently activate H2O2 to achieve hydroxyl radicals. This catalyst degrades Fast green dye efficiently around 89.3 % within 60 min with the optimum reaction conditions of 15 mM Fast Green dye, pH=4, 30 mg of Fe3O4‐biochar and 25 mM of H2O2. The composite shows around 41 % increase in the degradation rate after incorporating the Fe3O4 on biochar. The prepared Fe3O4‐biochar composite can be easily recycled without significant activity loss for five successive degradation reactions. The reported study provided a direction to prepare newer Fenton catalysts from sustainable sources for the degradation of organic dyes in water and overcame individual limitations of Fe3O4 and biochar. [ABSTRACT FROM AUTHOR]

WOx-promoted TiO2–ZrO2 solid acid catalyst was prepared and applied in the catalytic acetalization and ketalization of glycerol with carbonyl compounds to produce biofuel additives. The presence of WOx promoter and TiO2 remarkably improved the catalytic activity of ZrO2. Approximately, 100% glycerol conversion was evidenced with non-bulky aliphatic aldehydes and ketones like, propanol and cyclohexanone. The physical characterization of WOx-promoted TiO2–ZrO2, revealed a higher formation of tetragonal crystalline phase of ZrO2, over monoclinic. The total surface acidity and the ratio of Brønsted to Lewis acidic site concentrations were determined by NH3-TPD and pyridine-chemisorbed FTIR spectroscopy, respectively. A considerably higher concentration of Lewis acidic sites, ~ 213.29 μmol/gm, was evidenced on the WOx-promoted TiO2–ZrO2 catalyst surface. Catalytic activity study revealed a direct correlation between the surface Lewis acidic site concentration and the activity of catalyst. This significant observation indicated the key role of Lewis acidic sites in this catalytic process. The WOx-promoted TiO2–ZrO2 catalyst was also considerably stable and showed good performance in the acetalization/ketalization of glycerol with other substituted carbonyl compounds. The WOx-promoted TiO2–ZrO2 solid acid catalyst exhibits superior catalytic performance for acetalization and ketalization of glycerol with carbonyl compounds to produce biofuel additives. [ABSTRACT FROM AUTHOR]

Intramolecular charge transfer (ICT)-based chromophores are highly sought after for designing near-infrared (NIR) absorbing and emitting dyes as well as for designing materials for nonlinear optical (NLO) applications. The properties of these 'push-pull' molecules can easily be modified by varying the electronic donor (D) and acceptor (A) groups as well as the π-conjugation linker. This study presents a methodical approach and employs quantum chemical analysis to explore the relationship between the structural features, electro-optical properties, and the NLO characteristics of molecules with D-π-A framework. The one- and two-photon absorption (2PA), linear polarizability ( α ), and first hyperpolarizability ( β ) of some novel chromophores, consisting of a dimeric aza-Boron Dipyrromethene (aza-BODIPY) analogue, called, pyrrolopyrrole aza-BODIPY (PPAB), serving as the acceptor, have been investigated. The electronic donors used in this study are triphenylamine (TPA) and diphenylamine (DPA), and they are conjugated to the acceptor via thienyl or phenylene π-linkers. Additionally, the Hyper-Rayleigh Scattering ( β HRS ), which enables direct estimation of the second-order NLO properties, is calculated for the studied chromophores with 1064 nm excitation in acetonitrile. The β value shows a significant increase with increasing solvent polarity, indicating that the ICT plays a crucial role in shaping the NLO response of the studied molecules. The enhancement of the 2PA cross-section of the investigated molecules can also be achieved by modulating the combinations of donors and linkers. The results of our study indicate that the novel D-π-A molecules designed in this work demonstrate considerably higher hyperpolarizability values than the standard p -nitroaniline, making them promising candidates for future NLO applications., Competing Interests: The authors declare no competing financial interest., (This journal is © The Royal Society of Chemistry.)

Herein, the efficacy of WO x -promoted CeO 2 -SiO 2 and CeO 2 -ZrO 2 mixed oxide catalysts in the solvent-free selective oxidation of benzyl alcohol to benzaldehyde using molecular oxygen as an oxidant is reported. We evaluated the effects of the oxidant and catalyst concentration, reaction duration, and temperature on the reaction with an aim to optimize the reaction conditions. The as-prepared CeO 2 , CeO 2 -ZrO 2 , CeO 2 -SiO 2 , WO x /CeO 2 , WO x /CeO 2 -ZrO 2 , and WO x /CeO 2 -SiO 2 catalysts were characterized by X-ray diffraction (XRD), N 2 adsorption-desorption, Raman spectroscopy, temperature-programmed desorption of ammonia (TPD-NH 3 ), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). These characterisation results indicated that the WO x /CeO 2 -SiO 2 catalyst possessed improved physicochemical ( i.e. , structural, textural, and acidic) properties owing to the strong interactivity between WO x and CeO 2 -SiO 2 . A higher number of Ce 3+ ions ( I u''' / I Total ) were created with the WO x /CeO 2 -SiO 2 catalyst than those with the other catalysts in this work, indicating the generation of a high number of oxygen vacancies. The WO x /CeO 2 -SiO 2 catalyst exhibited a high conversion of benzyl alcohol (>99%) and a high selectivity (100%) toward benzaldehyde compared to the other promoted catalysts ( i.e. , WO x /CeO 2 and WO x /CeO 2 -ZrO 2 ), which is attributed to the smaller particle size of the WO x and CeO 2 and their high specific surface area, more significant number of acidic sites, and superior number of oxygen vacancies. The WO x /CeO 2 -SiO 2 catalyst could be quickly recovered and utilized at least five times without suffering any appreciable activity loss., Competing Interests: The authors declare no conflict of interest., (This journal is © The Royal Society of Chemistry.)