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The controlled synthesis of two‐dimensional nanocrystals of graphene particles instead of amorphous carbon quantum dots is highly challenging and requires tremendous efforts to optimize the reaction conditions. It has been observed that as a significant bio‐compatible zero‐dimensional material, graphene quantum dots are considered as a novel material for opto‐electronics, energy, biological and environmental applications. However, very few are known about their utilization in photocatalytic degradation of pesticides, especially organochlorine pesticides which are resistant to removal by conventional wastewater treatment methods. In this work, graphene quantum dots were produced from rice husk at relatively low temperatures, resulting in an average particle size of 3.3 nm. The high resolution transmission electron microscopy clearly showed the formation of spherical quantum dots having lattice fringes and the selected area electron diffraction pattern showed the crystallinity of the graphene quantum dots. A study of photodegradation of three highly toxic organochlorine pesticides namely, dichlorodiphenyl trichloro ethane, cypermethrin and fenvalerate were carried out using as‐synthesized graphene quantum dots from rice husk. Interestingly, all these pesticides were found to be degraded around 60 % to 70 % under visible light conditions. It confirmed that synthesized graphene quantum dots from rice husk can act as prominent photocatalyst for the degradation of pesticides and other pollutants. [ABSTRACT FROM AUTHOR]

Biodiesel has recently emerged as a renewable and environmentally benign fuel substitute for fossil‐derived energy sources. The use of heterogeneous solid catalysts for the generation of biodiesel from biomass‐derived fats and oils is sustainable. Among various reported catalyst supports, metal–organic frameworks (MOFs) have been popular choices for enhancing catalytic activity for biodiesel synthesis because of several outstanding features including porosity, high surface area, adjustable structures, and uniform pore sizes. In this research, the authors synthesized a novel nanocomposite of MOF‐supported hydroxyapatite (UiO‐66@HAp) using a facile impregnation technique and the characterization of the as‐synthesized catalyst was performed by different spectroscopic methods including powder X‐ray diffraction (PXRD), Fourier transform infrared (FTIR), X‐ray photoelectron spectroscopy (XPS), field emission gun‐scanning electron microscope (FEG‐SEM), energy dispersive X‐ray spectroscopy (EDS), high resolution transmission electron microscopy (HR‐TEM), thermogravimetric analysis (TGA), and N2 adsorption–desorption techniques. After successful synthesis, the catalytic property of the prepared material was evaluated in the palm oil transesterification into biodiesel. Product formation was confirmed by the 1H nuclear magnetic resonance (NMR) spectroscopy, 13C NMR, FTIR, and gas chromatography–mass spectrometry (GC–MS) of the biodiesel. The influence of different reaction variables such as catalyst dosage, methanol/oil molar ratio, temperature of the reaction, and reaction time was also studied. The outcomes revealed that the maximum biodiesel yield (∼97%) was obtained when 6 wt% catalyst was used with a 6:1 ratio of methanol/oil at 70 °C for 1 h. It was also observed that, even after 5 cycles of reuse, the catalyst was capable of producing significant amounts of biodiesel (over 90%). The results suggest that the synthesized novel catalyst holds a promising future in the sustainable production of biodiesel. [ABSTRACT FROM AUTHOR]

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]

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]

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]

Transition metal dichalcogenide (TMDC) nanotubes complement the field of low‐dimensional materials with their quasi‐1D morphology and a wide set of intriguing properties. By introducing different transition metals into the crystal structure, their properties can be tailored for specific purpose and applications. Herein, the characterization and a subsequent preparation of single‐nanotube field emission devices of MoxWx‐1S2 nanotubes prepared via the chemical vapor transport reaction is presented. Energy‐dispersive X‐ray spectroscopy, Raman spectroscopy, and X‐ray diffraction indicate that the molybdenum and tungsten atoms are randomly distributed within the crystal structure and that the material is highly crystalline. High resolution transmission electron microscopy and electron diffraction (ED) patterns further corroborate these findings. A detailed analysis of the ED patterns from an eight‐layer nanotube reveal that the nanotubes grow in the 2H structure, with each shell consists of one bilayer. The work function of the nanotubes is comparable to that of pure MoS2 and lower of pure WS2 NTs, making them ideal candidates for field emission applications. Two devices with different geometrical setup are prepared and tested as field emitters, showing promising results for single nanotube field emission applications. [ABSTRACT FROM AUTHOR]

Metal sulfides have shown great promise for sodium‐ion batteries due to their excellent redox reversibility and relatively high capacity. However, metal sulfides generally suffer from sluggish charge transport and serious volume change during the charge–discharge process. Herein, potato chip‐like nitrogen‐doped carbon‐coated ZnS/Sb2S3 heterojunction (ZnS/Sb2S3@NC) is precisely synthesized through a sulfurization reaction, and a subsequent metal cation exchange process between Zn2+ and Sb3+. The theoretical calculations and experimental studies reveal the boosted charge transfer in ZnS/Sb2S3@NC composites. Therefore, the ZnS/Sb2S3@NC electrode exhibits excellent cycling stability (a high reversible capacity of 511.4 mAh g‐1 after 450 cycles) and superior rate performance (400.4 mAh g‐1 at 10 A g‐1). In addition, ZnS/Sb2S3@NC is based on a conversion‐alloy reaction mechanism to store Na+, which is disclosed by the X‐ray diffraction and high resolution transmission electron microscopy analysis. This effective synthesis method can provide a reference for the design of other high‐performance electrode materials for sodium‐ion batteries. [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]

Understanding the mechanisms that connect heat and electron transport with crystal structures and defect chemistry is fundamental to develop materials with thermoelectric properties. In this work, we synthesized a series of self‐doped compounds Cu2+xMn1−xGeS4 through Cu for Mn substitution. Using a combination of powder X‐ray diffraction, high resolution transmission electron microscopy and precession‐assisted electron diffraction tomography, we evidence that the materials are composed of interconnected enargite‐ and stannite‐type structures, via the formation of nanodomains with a high density of coherent interfaces. By combining experiments with ab initio electron and phonon calculations, we discuss the structure–thermoelectric properties relationships and clarify the interesting crystal chemistry in this system. We demonstrate that excess Cu+ substituted for Mn2+ dopes holes into the top of the valence band, leading to a remarkable enhancement of the power factor and figure of merit ZT. [ABSTRACT FROM AUTHOR]

Understanding the mechanisms that connect heat and electron transport with crystal structures and defect chemistry is fundamental to develop materials with thermoelectric properties. In this work, we synthesized a series of self‐doped compounds Cu2+xMn1−xGeS4 through Cu for Mn substitution. Using a combination of powder X‐ray diffraction, high resolution transmission electron microscopy and precession‐assisted electron diffraction tomography, we evidence that the materials are composed of interconnected enargite‐ and stannite‐type structures, via the formation of nanodomains with a high density of coherent interfaces. By combining experiments with ab initio electron and phonon calculations, we discuss the structure–thermoelectric properties relationships and clarify the interesting crystal chemistry in this system. We demonstrate that excess Cu+ substituted for Mn2+ dopes holes into the top of the valence band, leading to a remarkable enhancement of the power factor and figure of merit ZT. [ABSTRACT FROM AUTHOR]

A novel 2‐D flakes like Al‐BPED ((N1,N2‐bis [pyridine‐2‐yl]methyl)ethane‐1,2‐diamine) metal–organic framework (MOF) have been explored for its catalytic potential in the N‐alkylation of amines with dialkyl carbonates. The Al‐BPED MOF catalyst has been synthesized by hydrothermal route. The X‐ray diffraction, Fourier Transform Infrared Spectroscope (FTIR), and High Resolution Transmission Electron Microscopy (HRTEM) images were used to analyze the morphology of the synthesized Al‐BPED MOF samples. With the use of Al‐BPED MOF, the primary and secondary aromatic amines were selectively and efficiently methylated with dimethyl carbonate. The effect of process conditions has been investigated toward N‐methylation, N‐ethylation, and N‐benzylation of aromatic amines. Under the optimal conditions with 10 mol% of the MOF catalyst, a maximum aniline conversion of 88% and a selectivity >90% toward N‐alkylation was achieved. The kinetic studies revealed the N‐alkylation reaction in presence of Al‐BPED MOF followed pseudo‐first order rate kinetics. [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]

Mechanical stirring of bulk Te in N‐methyl‐2‐pyrrolidone (NMP) solution at room temperature resulted in the formation of free‐standing few‐layer (∼1.2–2.8 nm) crystalline ultrathin nanosheets of tellurene with a large lateral thickness (∼1–1.6 μm) as confirmed by atomic force microscopy (AFM). High‐resolution transmission electron microscopy (HRTEM) confirms the presence of α‐ and β‐phases of tellurene. First‐principle density functional theoretical (DFT) based electronic structure calculations demonstrate the indirect band gap of bi‐layer β‐tellurene. The band gap decreases with increasing number of layers in the tellurene nanosheet. [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]

Herein we report a facile approach for the preparation of a magnetically separable Fe3O4@poly(m‐phenylenediamine)@Cu2O nanocatalyst and its catalytic efficiency in the synthesis of 5‐phenyl‐[1,2,3]triazolo[1,5‐c]quinazolines from (E)‐1‐bromo‐2‐(2‐nitrovinyl)benzenes, aldehydes, and sodium azide under mild reaction condition is described. The morphology, chemical composition, interior structure and magnetic properties of the Fe3O4@PmPDs@Cu2O nanocomposites were studied using powder X‐ray diffraction, scanning electron microscopy, high resolution transmission electron microscopy, energy dispersive X‐ray spectroscopy, X‐ray photoelectron microscopy, vibrating sample magnetometer and nitrogen adsorption‐desorption technique. The as‐prepared Fe3O4@PmPDs@Cu2O nanocatalyst was simply recovered using external magnet and reused up to successive six runs with no obvious loss in its catalytic efficiency and structural integrity (confirmed by powder X‐ray diffraction and transmission electron microscopy of recycled nanocatalyst) along with low leaching of copper (2.32 ppm) and iron (0.008 ppm) ions. The present protocol has a broad substrate scope with high yield in shorter reaction time and it does not require any additive or base. Overall, it has better green chemistry metrices like low E‐factor (0.93), process mass intensity (1.93), high reaction mass efficiency (51.9 %) and carbon efficiency (95 %). [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]

Cobalt oxide hydrate (Co(OH)x) supported on metal oxides were prepared. The oxidative cleavage of C(OH)−C bond in alcohol was catalyzed by Co(OH)x/metal oxides using molecular oxygen as the oxidant, and the corresponding product was obtained with high selectivity. The composition and characteristics of the catalysts were analyzed by X‐ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), high‐angle ring dark‐field scanning TEM (HAADF‐STEM), N2 physico‐adsorption characterization, inductively coupled plasma optical emission spectrometry (ICP‐OES), Fourier transform infrared spectrum (FTIR), X‐ray photoelectron spectroscopy (XPS) and NH3‐temperature‐programmed desorption (NH3‐TPD). Additionally, a reasonable reaction mechanism was proposed based on the characterization results and a series of controlled experiments. Notably, this heterogeneous catalytic system did not require any additives and had good recycling performance. [ABSTRACT FROM AUTHOR]

In this paper, sulfonic acid functionalize magnetic starch (denoted Starch/SPION@SO3H) is fabricated by the polymerization of 4‐styrenesulfonic acid on the surface of magnetic starch. Magnetic starch (Starch/SPION) is synthesized by covalent modification of starch by silica capsulate superparamagnetic iron oxide nanoparticles (SPION). For this purpose, Starch/SPION is modified by allyltrimethoxysilane, follows by the polymerization of 4‐styrenesulfonic acid onto this material. The catalyst is characterized by various characterization techniques, including transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), thermogravimetric analysis (TGA), vibrating‐sample magnetometer (VSM), X‐ray photoelectron spectroscopy (XPS), and acid/base titration. The characterizations prove the structure of Starch/SPION@SO3H catalyst. The catalytic activity of Starch/SPION@SO3H is evaluated in the multicomponent reaction of 4‐hydroxycoumarin, benzaldehydes, dimedone, and ammonium acetate for the synthesis of chromeno[4,3‐b]quinoline‐6,8(9H)‐dione derivatives. The catalyst shows very good activity in the synthesis of chromeno[4,3‐b]quinoline‐6,8(9H)‐dione derivatives. Several benzaldehydes with electron donating or electron withdrawing functionalities are used as starting material and all the substrates give the desired products in high isolated yields. In addition, the catalyst is extremely reusable during 10 sequential runs. Characterization of Starch/SPION@SO3H catalyst by TEM, VSM, and acid/base titration after recovery from the reaction proves the stability of the catalyst in the reaction conditions. [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]

In a sample with nominal composition BiCr2S5 a new misfit layer compound has been synthesized and studied via transmission electron microscopy (TEM). It presents a composite modulated structure with a composition that can be formulated as (BiS)1.19[(CrS2)‐Bi1/3‐(CrS2)]. It consists of the periodic stacking of a Q layer (BiS) with two H layers (CrS2), ...QHHQHH..., with additional bismuth atoms inserted between the H layers. Selected area electron diffraction (SAED) patterns show an almost commensurate fit between the pseudo‐tetragonal Q (BiS) and the pseudo‐orthohexagonal H (Bi1/3Cr2S4) subcells along the misfit direction a, being b the same for both sublattices and c the layers stacking direction. In addition to the characteristic misfit modulation between the two sub‐structures, a second modulation is observed in the H sub‐structure produced by the ordering of bismuth atoms within the Van der Waals gap that occurs between consecutive H layers. High resolution transmission electron microscopy (HRTEM) and scanning transmission electron microscopy (STEM) images show ordered stacking sequences between the (BiS) and (Bi1/3Cr2S4) layers. Besides, disordered intergrowths have been occasionally found as well as different kinds of twinning defects. [ABSTRACT FROM AUTHOR]

Silica‐bonded porous SiC ceramics were fabricated using nano‐β‐SiC powder‐carbon black template compacts by sintering in air at 600°C‐1200°C. The intrinsic microstructures of the porous ceramics were characterized by high‐resolution transmission electron microscopy, which led to the following observations: (a) a core (SiC)‐shell (SiO2) structure was formed, owing to the partial oxidation of nano‐SiC particles during sintering; (b) a low‐temperature (800°C) β‐to‐α polytypic phase transformation was observed, owing to the oxidation‐induced residual thermal stresses; and (c) non‐graphitic carbons were precipitated inside the SiC core, owing to the segregation of C atoms emitted at the strained SiC‐SiO2 interface. [ABSTRACT FROM AUTHOR]

We analyzed the surface atomic structure of highly oriented pyrolytic graphite (HOPG) substrate exfoliated with adhesive tape, using high‐resolution transmission electron microscopy and scanning transmission electron microscopy‐electron energy‐loss spectroscopy (STEM‐EELS). The surface step height of the exfoliated HOPG substrate was determined using high‐angle annular dark‐field‐scanning transmission electron microscopy (HAADF‐STEM) images and the depth profiles of the EELS spectra of a cross‐sectioned thin foil specimen prepared via focused ion beam milling. The exfoliated surface of the HOPG substrate presented disordered and curved graphene layers. The STEM‐EELS measurements indicated that upon exfoliation, the surface of the HOPG substrate reacted with atmospheric water and oxygen molecules. [ABSTRACT FROM AUTHOR]

Sol‐gel and hand milling techniques were used to prepare a lithium iron phosphate‐lithium manganese silicate (LiFePO4−Li2MnSiO4) hybrid cathode materials. The structural studies from x‐ray diffraction (XRD) and high resolution transmission electron microscopy (HRTEM) show that the materials are well crystallized although few impurities were observed in the pristine LiFePO4 (LFP) and Li2MnSiO4 (LMS) materials. We used graphene to coat the hybrid cathode materials in order to increase its conductivity and enhance the electrochemical performance. The successful reduction of the graphene oxide into graphene nanosheets was confirmed with the results from the Fourier transform infrared (FTIR) and Raman spectroscopy. The morphological analysis indicate that the pristine materials are made of spherical nanoparticles that are slightly agglomerated while the sol‐gel‐prepared hybrid cathode materials show evenly distributed spherical nanoparticles with minimal agglomeration. The in situ sol‐gel technique gave more homogenously mixed material in comparison to the hand milling method and particle sizes of 37 and 23 nm respectively were obtained for the plain, and graphenised sol gel derived hybrid materials. The sol‐gel derived hybrid materials are also the most thermally stable giving a total weight loss of 4.5 % and 3.4 % for the plain and graphenised cathodes respectively. While the LFP‐LMS hybrid cathode materials performed better electrochemically more than the pristine materials in terms of enhanced current and specific capacities, the graphenised LFP‐LMS hybrid cathode materials showed better electrochemical properties compared to those without graphene. This is associated with the presence of graphene nanosheets in these samples. All the results confirmed that the graphenised LiFePO4−Li2MnSiO4 hybrid cathode material prepared via in situ sol‐gel method performed better than those of the hand milling method. [ABSTRACT FROM AUTHOR]

Summary: This paper takes a fundamental view of the electron energy loss spectra of monolayer and few layer MoS2. The dielectric function of monolayer MoS2 is compared to the experimental spectra to give clear criteria for the nature of different signals. Kramers–Krönig analysis allows a direct extraction of the dielectric function from the experimental data. However this analysis is sensitive to slight changes in the normalisation step of the data pretreatment. Density functional theory provides simulations of the dielectric function for comparison and validation of experimental findings. Simulated and experimental spectra are compared to isolate the π and π + σ surface plasmon modes in monolayer MoS2. Single‐particle excitations obscure the plasmons in the monolayer spectrum and momentum resolved measurements give indication of indirect interband transitions that are excited due to the large convergence and collection angles used in the experiment. Lay Description: Two‐dimensional materials offer a path forward for smaller and more efficient devices. Their optical and electronic properties give way to beat the limits set in place by Moore's Law. Plasmon are the collective oscillations of electrons and can confine light to dimensions much smaller than its wavelength. In this work we explore the plasmonic properties of MoS2, a representational candidate from a family of 2D materials known as transition metal dichalcogenides. High resolution electron microscopy and spectroscopy provide insights in the plasmonic properties of MoS2 down to an atomic scale. Experimental results show the relationship between plasmons and interband transitions in the electron energy loss spectrum. Density functional theory provides a theoretical support for the experimental findings and provides commentary on the fundamental underlying physics. [ABSTRACT FROM AUTHOR]

Metal nanoparticles (NPs) in a transparent dielectric matrix represent a very intriguing system due to the plasmonic absorption tunable in the range of visible wavelengths. Herein, the preparation and physical characterization of plasmonic titania–silver dots thin films are reported. The synthesis parameter that leads to making a TiO2 matrix in which the Ag NPs are actually incorporated is carefully analyzed and controlled. Morphological (scanning electron microscopy, transmission electron microscopy, high resolution electron microscopy), structural (selected area diffraction, X‐ray diffraction), and spectroscopic (Raman spectroscopy) characterization techniques attest that the Ag NPs are spherical and homogeneously distributed into the TiO2 dielectric matrix in the structural modification of anatase. The study of the optical properties of films concludes the work. Plasmonic resonance is analyzed according to the light scattering theory. [ABSTRACT FROM AUTHOR]

A green nano‐sized ceramic pigment Co0.6Zn0.4Al0.8Cr1.2‐xSmxO4 has been successfully prepared by doping ions Zn2+, Cr3+, and Sm3+ into the crystalline CoAl2O4 spinel and using the complex‐gel method along with agar as complexing and combustion agent. The Infrared Spectroscopy, X‐ray diffraction, Thermo‐gravimeter, High resolution transmission electron microscopy, Automatic color reader, and UV Vis diffuse reflectance were applied to characterize the pigment power and its gel precursor. The results reveal that the introduction of Zn2+, Cr3+, and Sm3+ could change the occupation status of ions in the tetrahedral and octahedral framework of CoAl2O4 spinel, leading to the colorant variation of the blue cobalt pigment CoAl2O4, With increasing the content of Sm3+ ion, the reflection peak position of the pigments in visible spectrum appeared a red‐shift, ie the color transition from blue green to yellow green, and the average reflectivity in the violet region decreased to 13.31%, and the band gap energy also changed from 3.47 to 3.20 eV. This illustrates the better UV absorption of this green pigment and can be used as UV shielding material. With the hydrochloric acid or sodium hydroxide solution treatment, this pigment was found to be durable in chemical stability. [ABSTRACT FROM AUTHOR]

The active sites of Cu/ZnO‐based catalysts, commercially applied for the hydrogenation of CO2 or CO2‐rich synthesis gas, are still subject of current debates. Generally, the discussion is focused on the nature of the interfacial contact between Cu and ZnO, particularly whether it is rather of oxidic (Cu−ZnO) or alloying (Cu−Zn) character. We report on kinetic investigations on a Cu/ZnO : Al high performance catalyst activated at different temperatures. Incrementally increasing temperature under reductive conditions leads also to increased CuZn‐alloy formation, analyzed by in‐situ X‐ray diffraction, in‐situ X‐ray absorption spectroscopy and high resolution transmission electron microscopy. The combination of the catalytic data and the complementary characterization techniques provide valuable insights on the relevant reaction sites for CH3OH formation. Our results highlight the complexity of the interfacial contact with evidence for Cu−ZnO reaction sites and clarify the negative impact of CuZn alloy formation on the nature of the active site. [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]

Heterostructures of strongly correlated oxides demonstrate various intriguing and potentially useful interfacial phenomena. LaMnO3/SrMnO3 superlattices are presented showcasing a new high‐temperature ferromagnetic phase with Curie temperature, TC ≈360 K, caused by electron transfer from the surface of the LaMnO3 donor layer into the neighboring SrMnO3 acceptor layer. As a result, the SrMnO3 (top)/LaMnO3 (bottom) interface shows an enhancement of the magnetization as depth‐profiled by polarized neutron reflectometry. The length scale of charge transfer, λTF ≈2 unit cells, is obtained from in situ growth monitoring by optical ellipsometry, supported by optical simulations, and further confirmed by high resolution electron microscopy and spectroscopy. A model of the inhomogeneous distribution of electron density in LaMnO3/SrMnO3 layers along the growth direction is concluded to account for a complex interplay between ferromagnetic and antiferromagnetic layers in superlattices. [ABSTRACT FROM AUTHOR]

The LiRh‐type crystal structure of the equiatomic intermetallic compound IrZn turns out to be a competitor to the otherwise energetically favored CsCl‐type structures of congeneric transition metal zinc phases, thus enlightening the structural impact of element‐specific factors beyond the Hume‐Rothery concept. [ABSTRACT FROM AUTHOR]

A wide variety of pathogens causing nosocomial infections have emerged, showing resistance towards commonly used antimicrobial agents. Nosocomial infections are rapidly emerging as a severe threat leading to high morbidity and mortality. In this study, we have introduced Vancomycin grafted polydopamine(pDA) coated silver nanoparticles (AgNPs) to combat vancomycin‐resistant bacterial species Enterococci faecalis (E.faecalis). The prepared nanoparticles were characterized by High Resolution ‐Transmission Electron Microscopy (HR‐TEM), Energy Dispersive X‐ray Spectroscopy (EDS), Ultraviolet (UV) Visible spectroscopy and Attenuated Total Reflection‐Fourier Transform Infrared spectroscopy (ATR‐FTIR). The nanoparticles were 33 nm in size as revealed by HR‐TEM. Antimicrobial assays were conducted to investigate the antimicrobial activity of vancomycin‐pDA@AgNPs against E. faecalis by a zone of inhibition method. The vancomycin‐pDA@AgNPs exhibited good bactericidal activity against vancomycin‐resistant E. faecalis. [ABSTRACT FROM AUTHOR]

Highly functionalized reduced graphene oxide (rGO) sheets, decorated with homogenously distributed titanium dioxide (TiO2) nanoparticles, were obtained by optimizing the conditions of a facile solvothermal synthesis route with methanol‐water as solvent. These materials show a Raman enhancement apparently at the rGO/TiO2 interface. Conventional and High Resolution Transmission Electron microscopy (HRTEM) and X‐ray diffraction (XRD) show single crystal TiO2 NPs below 6 nm with an anatase crystalline phase. Fourier Transform Infrared (FT‐IR) spectroscopy shows a significant chemical reduction of the graphene oxide. Thermal analysis also confirms the efficient functionalization and in‐situ reduction of the graphene oxide sheets. The results show that under mild conditions, the solvent mixture achieves a higher functionalization than pure solvents. [ABSTRACT FROM AUTHOR]

Summary: Geometrical phase analysis (GPA) is typically a powerful tool to investigate the deformation in high resolution transmission electron microscopy images and has been used in various fields. During GPA, strain components are calculated relative to an undistorted reference region. In the present work, the effect of reference region size on strain measurements has been investigated. Experimental measurements on a locally distorted gold nanoparticle exhibited that a small reference region below the GPA spatial resolution can introduce an inaccuracy in the measured displacement field, which appears as a significant increase in measured strains and severe fluctuation in phase images. The inaccuracy may be ascribed to an error of insufficient sampling. Our results suggest that a small reference region below the GPA spatial resolution should be avoided during GPA. This prerequisite should be paid more attention to during strain measurement on nanoparticles. [ABSTRACT FROM AUTHOR]

Triflic acid functionalized carbon@silica composite (CStar@SiO2TfOH) was synthesized by the partial carbonization of starch in the presence of silica followed by the immobilization of triflic acid and its catalytic activity was explored for the three component synthesis of hexahydroacridine‐1,8‐diones and indeno[1,2‐b]indole‐9,10‐diones. CStar@SiO2‐TfOH was characterized using different techniques, such as Fourier‐Transform Infrared Spectroscopy (FTIR), Thermogravimetricanalysis (TGA), X‐ray Powder Diffraction (XRD), Energy Dispersive X‐ray (EDX), Scanning Electron Microscopy (SEM) and High Resolution Transmission Electron Microscopy (HR‐TEM) and was found to be recyclable upto five runs without any noticeable change. Further, the intermediate formed during the preparation of hexahydroacridine‐1,8‐dione has been isolated and its structure was confirmed by single crystal X‐ray crystallography which confirms the proposed mechanism. Also, to confirm the structure of 4b,9b‐dihydroxy‐5‐(4‐chlorophenyl)‐7,7‐dimethyl‐4b,5,7,8‐tetrahydroindeno[1,2‐b]indole‐9,10(6H,9bH)‐dione we have performed the DFT study and found that the 1H and 13C chemical shift values and IR wavenumbers predicted by B3LYP method were very close to the experimentally determined values. [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]

In this work, the influence of starting particle size and sintering conditions on the microstructures and dielectric properties of BaTiO3‐based ceramics coated with 0.3Bi(Zn1/2Ti1/2)O3‐0.7BaTiO3 were investigated to reveal the core‐shell structure by using high resolution transmission electron microscopy technique coupled with energy‐dispersive spectrometer analysis. The ion‐diffusion behavior plays a critical role in the formation and evolution of the core‐shell structure and, therefore, significantly influences the dielectric properties. When using starting powders containing BaTiO3 particles larger than 100 nm in size and sintering for shorter dwelling times (0.5‐2.0 hours), a core‐shell structure could be formed and retained owing to the limited diffusion behavior, enabling BaTiO3‐based ceramics to meet the X8R specification for multilayer ceramic capacitors applications at high temperatures. However, when using 80 nm BaTiO3 nanopowders and further extending the dwelling time to 6.0 hours, more driving energy was provided to prompt ion diffusion, which led to the compositional inhomogeneity becoming homogenized. [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]

As a potential remedy for addressing water scarcity challenges, advanced oxidation processes (AOP) present the opportunity of alleviating the water demand in water scarce regions. In this study appropriate doping of N and Pt into the titanium dioxide (TiO2) lattice using different dendrimers as templates and sources of nitrogen was demonstrated. The resulting N, Pt co‐doped TiO2 with small particle sizes was synthesized through a simple modified sol‐gel method. The N, Pt co‐doped TiO2 photocalysts were characterized through High Resolution Scanning Electron Microscopy (HR‐SEM) coupled with Energy Dispersive Spectroscopy (EDS), Transmission Electron Microscopy (TEM), Brunauer‐Emmett‐Teller  (BET), Raman Spectroscopy (RS), X‐ Ray Diffraction (XRD), Fourier‐transform Infrared Spectroscopy (FTIR), Thermo‐gravimetric analysis (TGA), Ultraviolet and visible (UV‐Vis) absorption spectroscopy  (UV‐Vis) and Photoluminescence (PL). The band gap reduction was more pronounced for the Poly (amidoamine) generation 1 (PAMAM G1) templated N, Pt co‐doped TiO2 (Eg=3.149 eV) compared to Poly (amidoamine) generation 0 (PAMAM G0) and Hyperbranched polyethylenimine (HPEI) templated N, Pt co‐doped TiO2. Co‐doping led to an enhancement in the photocatalytic activity of the photocatalysts for the degradation of brilliant black (99.83%) after 3 hours of visible light irradiation. Therefore, the synthesized photocatalysts can find applications in wastewater treatment using solar light. [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]

The study presents a novel paracetamol (PA) sensor based on Pd nanoparticles (PdNPs) deposited on carboxylated graphene oxide (GO−COOH) and nafion (Nf) modified glassy carbon electrode (GCE). The morphologies of the as prepared composites were characterized using high resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), X‐ray diffraction (XRD), X‐ray photoelectron spectroscopy (XPS), and fourier transform infrared spectroscopy (FTIR). The experimental results demonstrated that Nf/GO−COOPd displayed excellent electrocatalytic response to the oxidation PA. The linear range was 0.04–800 μM for PA with limit of detection of 0.012 μM and excellent sensitivity of 232.89 μA mM−1 cm−2. By considering the excellent performance of Nf/GO−COOPd composite such as wider linear range, lower detection, better selectivity, repeatability, reproducibility, and storage stability, the prepared composite, especially GO−COOH support, with satisfactory electrocatalytic properties was a promising material for the modification of electrode material in electrochemical sensor and biosensor field. [ABSTRACT FROM AUTHOR]

An electrochemical sensor for the simultaneous determination of Cd(II) and Pb(II) by square wave anodic stripping voltammetry (SWASV) in bivalve mollusks using a glassy carbon electrode modified with electrochemically reduced graphene oxide has been developed. The modified surface was characterized by cyclic voltammetry, high resolution scanning electron microscopy (HR‐SEM), and Raman spectroscopy. The optimum conditions were optimized and a linear range was observed from 15–105 μg L−1 with a limits of detection of 15 μg L−1 for Cd(II) and Pb(II). The methodology was validated and applied in different samples of commercial bivalve mollusks with satisfactory results. The high conductivity and greater surface area of the modifying agent improves the preconcentration capacity of the electrochemical sensor, allowing to develop a simple, rapid and sensitive analysis in the detection of lead and cadmium in marine resources. [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]

The capillary condensation is affected by micropore and nanopore of catalyst layer on fuel cell. Due to limitation of sluggish mass transport and electrocatalytic activity, to retain the pore skeleton of carbon and metal nanoparticles are very significant for enhanced utilizations of pore structure in electrochemical reaction. Besides, thickness of electrocatalyst layer is very crucial due to one of the factor affected by cell performance of direct methanol fuel cell. Highly loaded four Pt−Ru anode catalysts supported on resorcinol‐formaldehyde (RF) polymer based on meso‐porous carbons (80 wt.% Pt−Ru/carbon cryogel, 80 wt.% Pt−Ru/carbon xerogel and 80 wt.% Pt−Ru/carbon aerogel) and conventional carbon (80 wt.% Pt−Ru/Vulcan XC‐72) were prepared by colloidal method for direct methanol fuel cell. These catalysts were characterized by X‐Ray diffraction (XRD), High resolution transmission electron microscopy (HR‐TEM) and X‐ray photoemission (XPS). The results of CO stripping voltammetry, cyclic voltammetry (CV) and single cell test performed on DMFC show that Pt−Ru/carbon cryogel and Pt−Ru/carbon aerogel exhibits better performances in comparison to Pt−Ru/carbon xerogel and Pt−Ru/Vulcan XC‐72. It is thus considered that particle size, oxidation state of metal and electrochemical active surface area of these catalysts are important role in electrocatalytic activity in DMFC. [ABSTRACT FROM AUTHOR]