A series of copper sulfide (CS) nanoparticles (NPs) were synthesized just by varying the amount of sulfur precursor and have been explored for the first time as a three way...

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A promising strategy for the synthesis of pharmaceutically important scaffold 2,3-dihydroquinazolin-4(1H)-ones through heterogeneous catalysis employing the principle of multicomponent reaction has been presented in this paper. For the purpose, a...

Two classes of semiconductor copper sulfide (CS) nanostructures with a sheet-like architecture were designed via a hydrothermal route merely by varying the sulfur source concentration. The newly developed CS nanoparticles showed a breakthrough in catalytic performances and served as a very efficient, versatile, and recyclable multifunctional catalyst. The hexagonal plate-shaped pure covellite (CuS) phase of CS nanoparticles synthesized for this purpose showed excellent results, enabling complete removal of water pollutants [MB degradation and Cr(VI) reduction] under visible light irradiation within a few seconds of time. Contrarily, under ambient conditions, the mixed phase (covellite−digenite, CuS− Cu 1.8 S) with a broken nanosheet morphology was found to be a highly effective heterogeneous photocatalyst for the quantitative conversion of many aromatic and aliphatic alcohols to their respective aldehydes selectively. The direct band gaps of 2.06 and 1.90 eV calculated from UV−visible absorption spectroscopy data for CuS and CuS− Cu 1.8 S, respectively, suggested the semiconducting ability of the as-synthesized nanoparticles, which mainly assisted effortless visible light photocatalytic activity. Additionally, one more interesting development was achieved in this work: using CuS nanoparticles as a room-temperature catalyst for the oxidative hydroxylation of an array of arylboronic acid to prepare quantitative yields of corresponding phenols in a short period of time. Our designed catalyst outperforms most of the recently reported catalysts in terms of product yield and reaction time under mild reaction conditions in the synthesis of aromatic aldehydes and phenols. All the catalytic reactions were carried out at room temperature in this present work without using any expensive noble metals and harsh oxidizing agents. The enhacned catalytic performance of CS nanoparticles compared to that of other catalysts can be attributed to the size and specific composition and thereby the surface charge and exposed high energy facets of the nanoparticles due to the presence of sodium dodecyl sulfate as a surfactant in the synthetic procedure.

Aniline wastes can be converted to useful pharmaceutical and industrial compounds like azobenzene. For this purpose, a bimetallic Ag0.75Ni0.25 alloy is designed in the nanoscale range resembling a fivefold twinned morphology using water as the solvent. These newly developed alloy nanoparticles (NPs) are employed for the first time as an efficient visible light-active photocatalyst for the oxidative homocoupling of aniline to azobenzene. Our catalytic protocol is highly sustainable for a large number of aniline substrates with a high yield of the product (up to 95%), which might be attributed to the combinational and superior properties achieved on alloy formation in comparison to the monometallic counterparts. High-electron density amines (p-anisidine) display greater photocatalytic proficiency than that of low-electron density amines (4-fluoroaniline). The developed photocatalyst is magnetically well-separable and can be reused for at least five catalytic cycles without appreciable loss in its activity.