Topics in Catalysis最新文献

Nanotechnology advancements, notably in catalysis, have found several uses in the fabrication of heterocyclic molecules. An abundance nanoparticle (NPs) has been successfully used in a variety of organic transformations, which prompted us to undertake concentrated efforts to cover all instances in which gold nanoparticles (Au NPs) have been used in organic transformations. The catalytic application of gold nanoparticles in organic transformation has gained considerable interest researchers owing to its physical and chemical properties. Gold nanoparticles as catalysts in organic reactions deliver robust, green, and cost-effective alternatives for the synthetic transformations of heterocyclic scaffolds. Nitrogen- and oxygen-containing heterocyclic atoms are the essential prime units existing in diverse carbon-based vibrant lives and are substantial for industrial, pharmaceutical, and agrochemicals. Our focus will be on Au NP-catalyzed reactions in synthetic transformations for the production of heterocyclic scaffolds containing nitrogen and oxygen heteroatoms documented from 2011 to 2022. From a synthetic standpoint, this review will offer the reader an intrinsic framework for selecting the optimal Au NP catalytic system of importance for the synthesis of the preferred heterocyclic scaffold.

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Direct CO₂ hydrogenation into long-chain hydrocarbons over iron catalysts is considered the most promising approach to mitigate global warming issues. However, iron catalysts typically produce olefin-rich hydrocarbons, which make it difficult to directly use them as liquid transportation fuels. Here, we present a bimetallic Na–Fe_0.9Mg_0.1O_x catalyst that produced paraffin-rich long-chain hydrocarbons with a high C₅₊ yield of 17.9% at a high CO₂ conversion of 42.1%. The formation of oxygen vacant sites at the catalyst surface and electron transfer from MgO to Fe phase increased the reducibility of Fe₃O₄ to α–Fe. In addition, the presence of MgO increased the H₂ and CO₂ adsorption and facilitated the C–C coupling reaction to produce long-chain paraffins. The high CO₂ conversion, high C₅₊ yield, and paraffin-rich products make Fe_0.9Mg_0.1O_x a highly promising catalyst to produce liquid transportation fuels under industry-relevant conditions.

Ni-doped ZnO (NZO) thin films were prepared onto a glass substrate with varying concentrations of 2, 4, 6, 8, 10% of Ni using sol-gel spin coating method and their structural, optical and magnetic characteristics were discussed with supporting of XRD, UV, Photoluminescence, XPS and vibrating sample magnetometer (VSM) characterization techniques. The XRD analysis shows that the polycrystalline hexagonal wurtzite structure with (002) orientation of NZO thin films. The XPS results confirmed the presence of Ni ion in all the samples. The optical bandgap of the prepared samples was decreased with increasing concentrations of nickel from 3.33 to 3.22 eV. Photoluminescence spectra showed a red shift of near band edge (NBE) and deep level (DLE) emissions for prepared undoped and NZO thin films. The VSM of prepared NZO thin films exhibit ferromagnetic behavior at room temperature for potential applications in various fields. Our experimental observations support for transparent conducting electrode and spintronics device applications.

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Carbon nanodots were successfully prepared by a simple microwave-assisted method.

Carbon nanodots played a vital role in the improvement of the photocatalytic activity of TiO₂.

Photocatalytic removal of formaldehyde, acetone, and toluene was tested under humid conditions.

High catalytic stability in the degradation of formaldehyde was obtained on CDs/TiO₂.