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Many researchers have shifted their interest towards eco‐friendly, cost effective, and environmental‐based metal oxide nanoparticles. Herein, Cu2O nanoparticles are synthesized via green method for water splitting application. The prepared materials are characterized structurally and morphologically by field emission‐scanning electron microscopy (FESEM), high resolution transmission electron microscopy (HRTEM), X‐ray photoelectron spectroscopy (XPS) Raman, and UV–visible spectroscopy. It is found that size and morphology depend strongly on OLE concentration and reaction time. The temperature increase leads to the formation of copper oxide (CuO) nanoparticles, which exhibit quantum confinement behavior and have an optical band gap that increases with decreasing size. Photoelectrochemical (PEC) tests of the coated graphite with Cu2O nanoparticles show a severe instability of Cu2O under irradiation due to the oxidation state that can easily change. For that, a protective overlayer of cuprous sulfide Cu2S is successfully grown on the top of Cu2O nanostructures to stabilize the photocathode. After Cu2S deposition, the measured photocurrent is significantly improved. Thus, this material is very promising for hydrogen generation by water splitting. [ABSTRACT FROM AUTHOR]

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]

With an aim to combine the catalytic properties of Pd nanoparticles (NPs) with the excellent characteristics of porous layered double hydroxides (LDH), in the present study, four different catalysts (Pd/Fe3O4‐CoTiMgAlLDH, Pd/Fe3O4‐CoTiMgLDH, Pd/Fe3O4‐CoTiAlLDH and Pd/Fe3O4‐CoTiLDH) were synthesized by supporting Pd NPs onto four different Fe3O4‐LDH supports, which were synthesized by varying the metals in LDH. The catalytic activity of these catalysts was studied for Suzuki coupling and reductive degradation of dyes. Pd/Fe3O4‐CoTiMgLDH outperformed the other catalysts in both reactions. The synthesized catalysts were examined via different characterization techniques like X‐ray diffraction (XRD), Brunauer–Emmett–Teller analysis (BET), X‐ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), high resolution transmission electron microscopy (HR‐TEM), field emission scanning electron microscopy (FE‐SEM), energy dispersive X‐ray (EDX), energy dispersive X‐ray mapping (SEM–EDX mapping), inductively coupled plasma atomic emission spectroscopy (ICP‐AES) and vibrating sample magnetometry (VSM). On the basis of results obtained from XPS and the experimental data, Fe3O4‐CoTiMgLDH was found to be the support of choice as it not only stabilized the Pd0 NPs but also increased the electron density on the anchored Pd0 species, which enhanced the catalytic activity of Pd/Fe3O4‐CoTiMgLDH for studied organic transformations. [ABSTRACT FROM AUTHOR]

p‐Nitrophenol (p−NP) is a high priority toxic pollutant and that has harmful effects on human, animals and plants. Thus, the detection and determination of p−NP present in the environment is an urgent as well as highly important requisite. The present article, therefore focused on the construction of a novel electrochemical sensor based on NiO nanoparticles/α‐cyclodextrin functionalized reduced graphene oxide modified glassy carbon electrode (NiO−NPs‐α‐CD‐rGO‐GCE) for the selective and sensitive detection of p−NP. UV‐vis, high resolution transmission electron microscopy (HR‐TEM), selected area electron diffraction pattern (SAED) and X‐ray diffraction (XRD) analysis confirms the formation of highly pure NiO nanoparticles. Field emission scanning electron microscopy (FE‐SEM), energy dispersive X‐ray spectroscopy (EDS), and cyclic voltammetry (CV) were used to characterize the step‐wise electrode modification process. DPV was carried out to quantify p−NP within the concentration range of 1−10 μM and found the detection limit of 0.12 nM on the basis of the signal‐to‐noise ratio S/N=3. The electrode can able to detect different isomers of nitrophenols. Interferences of other pollutants such as phenol, p‐aminophenol, o‐ and m‐ nitrophenol, 4‐chlorophenol, 2,6‐dichlorophenol and ions like K+, Cd2+, Cl−, SO42− did not affect the sensing of p−NP. The newly developed sensor exhibited diffusion controlled kinetics and had excellent sensitivity, selectivity and reproducibility for the detection of p−NP. The electrode showed good recoveries in real sample analysis. [ABSTRACT FROM AUTHOR]

Cuboid‐shaped anatase TiO2 nanocrystals with co‐exposed {101} and [111]‐facets (or {101} and {100} facets), diamond‐shaped, rod‐like and irregular anatase TiO2 nanocrystals with dominant {010} facets were controllably synthesized from titanium (IV) ethoxide (TEOT) using HF as a capping agent via a facile sol‐gel procedure, and characterized by X‐ray powderdiffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), nitrogen adsorption, photoluminescence (PL) spectra, UV‐vis diffuse reflectance spectra,and electrochemical impedance spectroscopy (EIS). For the as‐prepared anatase TiO2 nanocrystals, the 0.5HF‐TiO2 revealed the best photocatalytic efficiency under UV light irradiation: 94.1 % of methylene blue (MB) was photodegraded within 90 min. The reaction rate constant k(min−1) was 1.39, 1.47, 1.59, 1.66, 1.92, 2.75, and 30.5 times higher than that of 2.0HF‐TiO2 (2.20×10−2 min−1), 1.5HF‐TiO2 (2.07×10−2 min−1), 1.0HF‐TiO2 (1.92×10−2 min−1), 2.5HF‐TiO2 (1.84×10−2 min−1), 3.0HF‐TiO2 (1.59×10−2 min−1), Bodi‐TiO2 (1.11×10−2 min−1), and the blank sample (0.10×10−2 min−1), respectively. Compared to other as‐prepared anatase TiO2 nanocrystals with the similar co‐exposed crystal facets, the highest efficiency of 0.5HF‐TiO2 could be attributed to the minimum crystal size,narrower pore size distribution, the maximum specific surface area, the lowest PL intensity and charge‐transfer resistance, andthe smallestrecombination resistance. [ABSTRACT FROM AUTHOR]

Summary: Regeneration of diesel particulate filter (DPF) is a complicated process due to its high operating temperature and associated oxidation of soot on the filter substrate. Several oxidation mechanisms of diesel soot have been proposed based on reaction kinetics, but more information about the oxidation phenomena is needed in a practical system, that is, soot oxidation on a DPF substrate. In this work, the DPF regeneration process was, for the first time, visualized at the particle scale ex‐situ, in time‐lapse series, using field emission scanning electron microscopy (FE‐SEM). Time‐lapse transformation of soot cake layer on a real DPF was followed from initiation through the complete regeneration process. In parallel, transformation of the soot primary particle diameter was directly measured using high‐resolution transmission electron microscopy. FE‐SEM visualization clearly showed shrinkage of the soot cake layer on the DPF wall as oxidation progressed. Furthermore, diameter distribution analysis revealed a trend of shrinkage of the nanoscale soot primary particles during oxidation, supporting the FE‐SEM observations of the micron‐scale shrinkage of the agglomerated soot cake layer. Fragmentation of the shrunken soot cake layer was also observed and is suspected to be a result of locally higher gas flow that depends on surface pore morphology of the filter substrate. Lay Description: In this work, the DPF regeneration process was, for the first time, visualized at the particle scale ex‐situ, in time‐lapse series, using field emission scanning electron microscopy (FE‐SEM). Time‐lapse transformation of soot cake layer on a real DPF was followed from initiation through the complete regeneration process. In parallel, transformation of the soot primary particle diameter was directly measured using high resolution transmission electron microscopy. FE‐SEM visualization clearly showed shrinkage of the soot cake layer on the DPF wall as oxidation progressed. Furthermore, diameter distribution analysis revealed a trend of shrinkage of the nano‐scaled soot primary particles during oxidation, supporting the FE‐SEM observations of the shrinkage of the micron‐scale agglomerated soot cake layer. Fragmentation of the shrunken soot cake layer was also observed and is suspected to be a result of locally higher gas flow that depends on surface pore morphology of the filter substrate. Further detail mechanism about transformations of the soot cake layer was additionally discussed based on electrostatic attraction. [ABSTRACT FROM AUTHOR]

In this work, dehydrogenation of NaBH4 in alkaline solutions was catalyzed by amorphous Co‐B catalysts supported on nitrogen doped carbon (N‐C) that is rarely utilized in this field. The physicochemical properties of the as‐prepared catalysts were characterized by X‐ray Diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM), High Resolution Transmission Electron Microscopy (HRTEM), X‐ray Photoelectron Spectroscopy (XPS), Raman Spectroscopy and BET (Brunner−Emmet−Teller) measurements. Among all the catalysts made in this paper, Co‐B/N‐C‐700 exhibited best activity, which is likely to be attributed to the possession of more metal Co as active sites. The hydrogen generation rate (HGR) reached 2649 ml H2 min−1 g−1cat in 10 wt. % NaOH + 10 wt. % NaBH4 solution at 30 °C. The value of activation energy is 37.57 kJ mol−1 and compares favorably with values of some previous reports. Besides, influences of NaOH concentration, NaBH4 concentration, temperature, recycle times and amount of catalyst for the catalytic performance of Co‐B/N‐C‐700 were also investigated to reflect more on hydrolysis of sodium borohydride. [ABSTRACT FROM AUTHOR]

Aided by our interest in green chemistry, we report the synthesis of a novel Pd‐Sn nano catalyst for C−N coupling reaction in water. The catalyst has been synthesized by a simple wet chemical reduction method and fully characterized by a library of physico‐chemical techniques such as Powder X‐Ray Diffraction (PXRD), High Resolution Transmission Electron Microscopy (HRTEM), X‐Ray Photo Electron Spectroscopy (XPS) and UV‐Vis spectroscopy, Field Emission Scanning Electron Microscopy (FESEM), Energy Dispersive X‐Ray (EDX) spectroscopy, and Inductively Coupled Plasma Optical Emission Spectroscopy (ICP‐OES). The robust Pd‐Sn catalyst shows high catalytic efficiency for the oxidative coupling of benzylamines and tandem coupling between alcohol and amine in water as solvent to give rise to the corresponding secondary amines. However, in presence of oxygen both the reactions stop at the imine stage. As a result, we could guide the reaction to obtain selectively amine or imine. The high efficiency, recyclability and good substrate scope of this Pd‐Sn nanocatalyst is noteworthy. Preliminary mechanistic studies indicated that the reactions proceed via initial activation of N−H bond of amine [ABSTRACT FROM AUTHOR]

A novel ecofriendly Ca nanoparticle bridged aminoclay (AC) catalyst was prepared for the reduction of hazardous pollutants to treat the industrial wastewater. It was characterized by FT‐IR spectroscopy, UV‐visible spectroscopy, X‐ray diffraction (XRD), X‐ray photoelectron spectroscopy (XPS), high resolution transmission electron microscopy (HRTEM), field emission scanning electron microscopy (FESEM), energy dispersive X‐ray spectrum (EDX), differential scanning calorimetry (DSC), and thermogravimetry (TG) techniques. Water contact angle (WCA) measurement was used to confirm the hydrophobicity of AC after the structural modification reaction. Disappearance of free N−H stretching in the FT‐IR spectrum confirmed the chemical modification of AC by Ca nanoparticle. The above‐synthesized Ca nanoparticle bridged AC was used as a catalyst for the reduction of p‐nitrophenol (NP), chromium (VI) and fluorescein (fluor) dye and also for oxidative Schiff base formation. The UV‐visible spectrum confirmed the complex formation between chromium (VI) and NP by noting a peak at 390 nm. The kapp value was computed to assess the efficiency of the catalyst toward the reduction of hazardous pollutants in the industrial effluents. The catalytic reduction of a tricomponent system is disturbed due to the change in pH and complex formation between the pollutants, etc. The present catalyst system reduced the two‐step reaction into a single‐step reaction for the Schiff base formation. [ABSTRACT FROM AUTHOR]

In this present study, we have shown dopamine acts as very good agent in killing cancer cells with very high rate. We have used silica coated iron oxide magnetic particles as dopamine drug delivery agent. We have synthesized iron oxide (Fe3O4) magnetic nanoparticles (MNPs), and coated it with silicon dioxide (SiO2), then loaded it with dopamine (DA) which has been used here as anticancer drug. Here a significant improvement was found in case of drug release under acidic pH than normal blood pH. The MNPs are characterized using X‐ray diffraction (XRD), Energy Dispersive Analysis of X‐rays (EDAX), Fourier transform infrared (FTIR), Field Emission Scanning Electron Microscopy (FESEM), Transmission Electron Microscopy (TEM), High Resolution Transmission Electron Microscopy (HRTEM), Selected Area Electron Diffraction (SAED) and vibrating sample magnetometer (VSM) to confirm its structural, morphological and magnetic properties. Particles after characterization were involved in investigation of DA drug release by altering pH for better treatment of cancer. The results are very important and promising. [ABSTRACT FROM AUTHOR]

A unique brush coating technique was adopted to prepare high microwave absorbing super‐hydrophobic bactericidal fabrics. 3D micro‐CT, field emission scanning electron microscopy (FE‐SEM) and high resolution transmission electron microscopy (HR‐TEM) analyses were employed to establish the composite morphology. X‐ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) were used to characterize the embedded silver nanoparticles in the cotton fabrics. The developed thin wearable coated fabrics hold the lowest resistivity of 8 ohm‐cm−2 (lighten up series of LEDs) and electromagnetic interference (EMI) shielding effectiveness (SE) of 30.07 dB at 0.3 mm coating thickness within the X‐band frequency range. These thin coated fabrics can be the used in the flexible electronic devices along with extreme bactericidal feature against E. coli. [ABSTRACT FROM AUTHOR]