Search

The present study was focused on green synthesis of Silver nanoparticles (AgNPs) using Trigonella foenum‐graceum L. seed extract belonging to specific variety HM (Hisar Mukta) 425, optimizing the different experimental conditions required for the formation and stability of AgNPs. UV‐Vis spectroscopy, Particle Size Analyzer (PSA), Field Emission Scanning Electron Microscopy (FESEM), High Resolution Transmission Electron Microscopy (HRTEM), X‐ray diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) were used to characterise the synthesised AgNPs. The average size of AgNPs was found to be 22 nm and were spherical in shape. Additionally, the United States Environmental Protection Agency (USEPA) has listed nitrophenols as a priority pollutant, and biosynthesized AgNPs can catalytically convert them into less harmful aminophenols. One example of a reaction where AgNPs are used as a catalyst is the conversion of p‐nitrophenol to p‐aminophenol, which acts as a bridge for many analgesics and antipyretic medications. Hence, the study is anticipated to have a significant impact on the pharmaceutical, cosmetic, and food industries. [ABSTRACT FROM AUTHOR]

Environmental remediation projects are becoming increasingly interested in polymers, transition‐metal oxides and graphene based nanocomposites as photocatalysts. To increase their effectiveness, they could be adjusted in conjunction with one another. A hierarchically organised nanocomposite of reduced graphene oxide based TiO2 and copolymer (Aniline and Indole) (rGO/ TiO2/P(ANI‐co‐IN)), TiO2/P(ANI‐co‐IN) and P(ANI‐co‐IN) has been synthesized by heterogeneous emulsion polymerization and is used as a catalyst for the degradation of the cationic Rhodamine (RhB) dye. Different analyses were used to characterize the resulting nanocomposites i. e. UV‐Vis diffuse reflectance spectra (DRS), Fourier Transform Infrared spectroscopy (FTIR), X‐ray diffraction (XRD), Energy Dispersive X‐Ray Spectroscopy (EDX), High Resolution Transmission electron microscopy (HR‐TEM), Selected area (electron) diffraction (SAED) and thermogravimetric analysis (TGA). DRS results revealed that the rGO/ TiO2/ P(ANI‐co‐IN) nanocomposites band gap decreased when compared to TiO2/P(ANI‐co‐IN) and P(ANI‐co‐IN). Here, rGO/ TiO2/P(ANI‐co‐IN) has outperformed every previous study on polymer/metal oxide/graphene‐based ternary nanocomposites, achieving 92 % RhB degradation within 80 min with a degradation rate constant of 0.032 min−1. The reusability of rGO/ TiO2/P(ANI‐co‐IN) was run over five cycles which bought in only a small change which could be negligible. Overall, this research may make it easier to synthesise hierarchically organised ternary nanocomposites in the future, which might be used to improve photocatalysis and address environmental protection challenges. [ABSTRACT FROM AUTHOR]

Low loading Pton TiO2 were prepared by an impregnation‐reduction process for chemoselective hydrogenation of chloronitrobenzenes (CNBs) to chloroanilines (CANs). The structure and physicochemical properties were characterized by N2 adsorption‐desorption, X‐ray diffraction, high resolution transmission electron microscopy, X‐ray photoelectron spectroscopy and temperature programmedreduction. The low loading Pt(≤0.08 wt %) on TiO2 exhibited outstanding chemoselectivity for the catalytic hydrogenation of CNBs to CANs, without any disturbance on carbon‐chlorine bond. The characterization data suggested that the Pt particles were highly dispersed on TiO2 and strongelectronicinteractionsoccur between the dispersedPt andTiO2support, which led toelectron deficiency of nearly all Pt and production of suboxide TiOx species (x<2) in the 0.08 wt % Pt/TiO2. The electron‐deficient Pt and suboxide TiOx species favor N=O bondactivation, leading to its unique chemoselectivity. [ABSTRACT FROM AUTHOR]

Ni nanoparticles (NiNPs) were prepared by thermal decomposition of nickel acetylacetonate in the presence of a third generation polypyridylphenylene dendrimer (G3) which acts both as a coordinating ligand due to presence of pyridine groups and as a stabilizing agent due to highly branched architecture. Transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), and X‐ray photoelectron spectroscopy (XPS) were used to extensively evaluate structure and morphology of the synthesized NiNPs@G3. The selected area electron diffraction (SAED) allowed us to conclude about fcc structure of NiNPs while STEM EDS analysis demonstrated a formation of core‐shell NiO@Ni NPs. Further, the catalyst was tested in selected Suzuki‐Miyaura cross‐coupling reactions at mild conditions and demonstrated a high efficiency at low Ni loading with negligible content of Ni0 on the NP surface. The functional hyperbranched dendrimer macromolecule provided an excellent stabilization for NiNPs@G3 while allowing an easy access for reactants to catalytic sites. The high activity of the catalyst in the recycling experiments was maintained by the absence of Ni leaching from the NiNPs@G3. [ABSTRACT FROM AUTHOR]

The development of bimetallic and magnetic nanomaterials as a catalyst is highly desirable for organic transformations due to their recyclability for the sustainable future of chemical industries. Bimetallic CoNi nanoflowers were developed via the facile liquid‐phase reduction method and were employed for the hydrogenation of terminal alkynes. The structural and morphological studies were analyzed by X‐ray diffraction, Field‐Emission Scanning Electron Microscopy, and High Resolution Transmission Electron Microscopy. The bimetallic CoNi nanoflower exhibited 100 % conversion with ∼100 % selectivity towards alkane products with recyclability up to six cycles. The transfer hydrogenation mechanism was proposed via diimide formation with Co(0)/Ni(0) state, confirmed by X‐ray Photoemission Spectroscopy analysis. [ABSTRACT FROM AUTHOR]

This study explains the synthesis of cobalt‐doped dysprosium oxide nanocubes (Co‐Dy2O3 NCs) and the modification of GCE (glassy carbon electrode), for the selective and sensitive detection of riboflavin (RF). The Co‐Dy2O3 NCs were synthesized by co‐precipitation method and characterized using spectroscopic and microscopic techniques like micro‐Raman Spectroscopy, X‐ray diffraction (XRD), X‐ray Photoelectron Spectroscopy (XPS), Fourier Transform Infrared Spectroscopy (FT‐IR), High‐Resolution Transmission Electron Microscopy (HRTEM), Energy‐Dispersive X‐ray Spectroscopy (EDX), and High Resolution Scanning Electron Microscopy (HRSEM). The synthesized Co‐Dy2O3 NCs were coated on the glassy carbon electrode to detect and quantify the concentration of riboflavin in aqueous and real samples. The samples were analyzed by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) techniques with three‐electrode system. The modified electrode displays two linear concentration ranges (0.5–50, 50–300 μM) with a low detection limit (LOD) of 0.094 μM and high sensitivity of 3.67 μA μM−1 cm−2. Besides, the fabricated sensor has more selectivity, great reproducibility, repeatability and good stability. Finally, the Co‐Dy2O3 NCs modified GCE based sensor was effectively applied in real sample analysis using milk and egg yolk with good recovery. [ABSTRACT FROM AUTHOR]

The current study focuses on the photocatalytic reduction of p‐nitrophenol using Europium, Yttrium and Lutetium doped Cerium oxide (CeO2) nanoparticles which were synthesized via chemical precipitation method. The synthesized nanoparticles were subjected to characterization using different analytical tools to confirm the formation of nanoparticles. They were characterized using X‐Ray diffraction (XRD) studies, Fourier Transform‐Infrared spectroscopy (FT‐IR), High resolution Scanning electron microscopy (HRSEM), High resolution Transmission electron microscopy (HRTEM), Energy dispersive X‐ray analysis (EDAX), X‐ray photoelectron spectroscopy (XPS), and UV‐Diffuse reflectance spectroscopy (UV‐DRS) studies. The synthesized rare earth nanomaterials were successfully applied for the photoreduction of the organic pollutant p‐nitrophenol with the addition of NaBH4 as reducing agent using 300 W Xenon lamp. The addition of the synthesized photocatalyst enhanced the reduction ability of NaBH4 in reducing p‐nitrophenol to p‐aminophenol. The results confirmed the superior photocatalytic activity of Lu0.05CeO2 compared to the other rare earth doped photocatalysts. The time taken by Lu0.05CeO2 photocatalyst for the complete reduction of p‐nitrophenol was 45 min and was found to be 96 % efficient in the reduction of 0.5 mM p‐nitrophenol to p‐aminophenol compared to the other photocatalysts. [ABSTRACT FROM AUTHOR]

In the present work, we have demonstrated the synthesis of Molybdenum Carbide‐reduced graphene oxide (Mo2C‐rGO) heterostructure. Uniquely, the in‐situ formation of rGO using D‐glucose in the heterostructure and its battery performance has been discussed. The High Resolution Transmission Electron Microscopy (HR‐TEM) study clearly shows the growth of Mo2C nanoparticles along with rGO confers a unique integrated layered heterostructure. X‐ray diffraction (XRD) and Raman study exhibits the formation of graphene oxide (GO) followed by multi‐layers of rGO along with hexagonal Mo2C. The electrochemical study of Mo2C‐rGO heterostructure demonstrates stable cycling performance and excellent rate capabilities. The heterostructure showed the initial capacity (1st discharge) around 632.23 mAh/g and specific capacity i. e., 537.91 mAh/g @ 0.5 A/g with 99–100 % columbic efficiency. The reversible capacities of 521.56 mAh/g, and 400.76 mAh/g were observed at current densities of 1 A/g and 2 A/g for 300 cycles, respectively, which justifies the stability of heterostructure. The cycled cell was investigated by using Electrochemical Imepedance Spectroscopy (EIS), ex‐situ XRD, and Field Emmision Scanning Electron microscopy (FESEM), which shows the negligible change in the ionic conductivity, structure, and morphology after 300 cycles. It shows the excellent stability of Mo2C‐rGO heterostructure. [ABSTRACT FROM AUTHOR]