Preparation and characterization of block copolymers containing cinnamate groups with end-capped ZnO

AbstractAbstract ZnO-poly(2-cinnamoyloxyethyl methacrylate) and ZnO-poly(2-cinnamoyloxyethyl methacrylate)-b-poly[(poly(ethylene glycol) methyl ether methacrylate] have been prepared by atom transfer polymerization initiated through a 2-bromoisobutyryl or bromoethyl group linked onto the ZnO nanoparticle surface (ZnO-BIBB, ZnO-BEI). The structure and morphology of the hybrids were characterized using Fourier transform infrared, proton nuclear magnetic resonance, fluorescence and UV spectroscopy, thermogravimetric analysis, X-ray photoelectron spectroscopy, X-ray diffraction, transmission electron (TEM) and atomic force microscopy. The existence of nanoparticles with diameters varying between 40 and 100 nm was evident in the TEM images of the pure ZnO, ZnO-PCEMA-Br-2 and the diblock copolymer. Under an excitation of 340 nm, these materials exhibit a broad emission band at around 390 nm, which was associated with the presence of ZnO in the organic matrix. Graphical abstract

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Reliable Solvothermal Growth of Diverse Heterostructures Based on CdS Nanowires

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.887-888.174 ◽

2014 ◽

Vol 887-888 ◽

pp. 174-180

Author(s):

Fan Yang ◽

Shan Cheng Yan ◽

Bo Jun Wang ◽

Zhen Hua Shuai ◽

Ming Xia Zhang

Keyword(s):

Electron Microscopy ◽

Photoelectron Spectroscopy ◽

Semiconductor Heterostructures ◽

Zno Nanoparticle ◽

Solvothermal Process ◽

X Ray Diffraction ◽

X Ray ◽

Cds Nanowire ◽

Transmission Electron ◽

Cds Nanowires

In the present study, the heterostructures of ZnO Nanoparticle (NP)/CdS nanowire (NW), SnO2NP/CdS NW, NiS NP/CdS NW, FeS NP/CdS NW, Ag2S NP/CdS NW, and Au NP/CdS NW have been successfully fabricated via the two-stage solvothermal process. Field-emission scan electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) were adopted to characterize the as-prepared products. The optical properties of the as-obtained heterostructures were separately investigated. New insights into understanding and controlling the synthesis of different NW heterostructures are demonstrated in the reliable solvothermal route. We demonstrate that CdS NWs synthesized for 2h are the bifunctional mediator acting as catalyst or active spot for the growth of NW heterostructures Furthermore, understanding and controlling this phenomenon is a great asset for the realization of the formation mechanism of the NW heterostructures and opens up new ways toward for construction of other semiconductor heterostructures with novel properties.

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α-Cellulose Fibers of Paper-Waste Origin Surface-Modified with Fe3O4 and Thiolated-Chitosan for Efficacious Immobilization of Laccase

Polymers ◽

10.3390/polym13040581 ◽

2021 ◽

Vol 13 (4) ◽

pp. 581

Author(s):

Gajanan S. Ghodake ◽

Surendra K. Shinde ◽

Ganesh D. Saratale ◽

Rijuta G. Saratale ◽

Min Kim ◽

...

Keyword(s):

Enzyme Immobilization ◽

Photoelectron Spectroscopy ◽

Cellulose Fibers ◽

Relative Activity ◽

Significant Activity ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Laccase Immobilization ◽

Surface Modified

The utilization of waste-paper-biomass for extraction of important α-cellulose biopolymer, and modification of extracted α-cellulose for application in enzyme immobilization can be extremely vital for green circular bio-economy. Thus, in this study, α-cellulose fibers were super-magnetized (Fe3O4), grafted with chitosan (CTNs), and thiol (-SH) modified for laccase immobilization. The developed material was characterized by high-resolution transmission electron microscopy (HR-TEM), HR-TEM energy dispersive X-ray spectroscopy (HR-TEM-EDS), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared spectroscopy (FT-IR) analyses. Laccase immobilized on α-Cellulose-Fe3O4-CTNs (α-Cellulose-Fe3O4-CTNs-Laccase) gave significant activity recovery (99.16%) and laccase loading potential (169.36 mg/g). The α-Cellulose-Fe3O4-CTNs-Laccase displayed excellent stabilities for temperature, pH, and storage time. The α-Cellulose-Fe3O4-CTNs-Laccase applied in repeated cycles shown remarkable consistency of activity retention for 10 cycles. After the 10th cycle, α-Cellulose-Fe3O4-CTNs possessed 80.65% relative activity. Furthermore, α-Cellulose-Fe3O4-CTNs-Laccase shown excellent degradation of pharmaceutical contaminant sulfamethoxazole (SMX). The SMX degradation by α-Cellulose-Fe3O4-CTNs-Laccase was found optimum at incubation time (20 h), pH (3), temperatures (30 °C), and shaking conditions (200 rpm). Finally, α-Cellulose-Fe3O4-CTNs-Laccase gave repeated degradation of SMX. Thus, this study presents a novel, waste-derived, highly capable, and super-magnetic nanocomposite for enzyme immobilization applications.

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Novel Carbon Dots Derived from Glycyrrhizae Radix et Rhizoma and Their Anti-Gastric Ulcer Effect

Molecules ◽

10.3390/molecules26061512 ◽

2021 ◽

Vol 26 (6) ◽

pp. 1512

Author(s):

Yuhan Liu ◽

Meiling Zhang ◽

Jinjun Cheng ◽

Yue Zhang ◽

Hui Kong ◽

...

Keyword(s):

Gastric Ulcer ◽

Photoelectron Spectroscopy ◽

Carbon Dots ◽

High Performance ◽

Raw264.7 Cells ◽

Mice Model ◽

X Ray ◽

Glycyrrhizae Radix ◽

Transmission Electron ◽

High Resolution Tem

Glycyrrhizae Radix et Rhizoma (GRR) is one of the commonly used traditional Chinese medicines in clinical practice, which has been applied to treat digestive system diseases for hundreds of years. GRR is preferred for anti-gastric ulcer, however, the main active compounds are still unknown. In this study, GRR was used as precursor to synthesize carbon dots (CDs) by a environment-friendly one-step pyrolysis process. GRR-CDs were characterized by using transmission electron microscopy, high-resolution TEM, fourier transform infrared, ultraviolet-visible and fluorescence spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction and high-performance liquid chromatography. In addition, cellular toxicity of GRR-CDs was studied by using CCK-8 in RAW264.7 cells, and the anti-gastric ulcer activity was evaluated and confirmed using mice model of acute alcoholic gastric ulcer. The experiment confirmed that GRR-CDs were the spherical structure with a large number of active groups on the surface and their particle size ranged from 2 to 10 nm. GRR-CDs had no toxicity to RAW264.7 cells at concentration of 19.5 to 5000 μg/mL and could reduce the oxidative damage of gastric mucosa and tissues caused by alcohol, as demonstrated by restoring expression of malondialdehyde, superoxide dismutase and nitric oxide in serum and tissue of mice. The results indicated the explicit anti-ulcer activity of GRR-CDs, which provided a new insights for the research on effective material basis of GRR.

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Highly active carbon nanotube–promoted Rh-Mn-Li/SiO2 catalysts for the synthesis of C2+ oxygenates from syngas

Journal of Chemical Research ◽

10.1177/1747519820984728 ◽

2021 ◽

pp. 174751982098472

Author(s):

Jun Yu ◽

Ying Han ◽

Guoqing Chen ◽

Xiuzhen Xiao ◽

Haifang Mao ◽

...

Keyword(s):

Carbon Nanotubes ◽

Photoelectron Spectroscopy ◽

Co Hydrogenation ◽

X Ray ◽

Highly Active ◽

Transmission Electron ◽

Co Insertion ◽

Temperature Programmed Surface Reaction ◽

Temperature Programmed ◽

Oxygenate Synthesis

The effect of carbon nanotubes on the catalytic properties of Rh-Mn-Li/SiO2 catalysts was investigated for CO hydrogenation. The catalysts were comprehensively characterized by means of X-ray power diffraction, N2 sorption, transmission electron microscope, H2–temperature-programmed reduction, CO–temperature-programmed desorption, temperature-programmed surface reaction, and X-ray photoelectron spectroscopy. The results showed that an appropriate amount of carbon nanotubes can be attached to the surface of the SiO2 sphere and can improve the Rh dispersion. Moderate Rh-Mn interaction can be obtained by doping with the appropriate amount of carbon nanotubes, which promotes the formation of strongly adsorbed CO and facilitates the progress of CO insertion, resulting in the increase in the selectivity of C2+ oxygenate synthesis.

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Synthesis, characterization and in vitro cytotoxicity study of Co and Ni ferrite nanoparticles prepared by sol-gel method

SN Applied Sciences ◽

10.1007/s42452-021-04709-y ◽

2021 ◽

Vol 3 (7) ◽

Author(s):

Alexandre Pancotti ◽

Dener Pereira Santos ◽

Dielly Oliveira Morais ◽

Mauro Vinícius de Barros Souza ◽

Débora R. Lima ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

Sol Gel ◽

Test Sample ◽

In Vitro Cytotoxicity ◽

Gel Method ◽

X Ray ◽

Sol Gel Method ◽

Transmission Electron ◽

Crystallite Sizes

AbstractIn this study, we report the synthesis and characterization of NiFe2O4 and CoFe2O4 nanoparticles (NPs) which are widely used in the biomedical area. There is still limited knowledge how the properties of these materials are influenced by different chemical routes. In this work, we investigated the effect of heat treatment over cytotoxicity of cobalt and niquel ferrites NPs synthesized by sol-gel method. Then the samples were studied using transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), vibrating sample magnetometer (VSM), Fourier Transform Infrared Spectroscopy Analysis (FTIR), and X-ray fluorescence (XRF). The average crystallite sizes of the particles were found to be in the range of 20–35 nm. The hemocompatibility (erythrocytes and leukocytes) was checked. Cytotoxicity results were similar to those of the control test sample, therefore suggesting hemocompatibility of the tested materials.

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Surface Stoichiometry and Depth Profile of Tix-CuyNz Thin Films Deposited by Magnetron Sputtering

Materials ◽

10.3390/ma14123191 ◽

2021 ◽

Vol 14 (12) ◽

pp. 3191

Author(s):

Arun Kumar Mukhopadhyay ◽

Avishek Roy ◽

Gourab Bhattacharjee ◽

Sadhan Chandra Das ◽

Abhijit Majumdar ◽

...

Keyword(s):

Magnetron Sputtering ◽

Photoelectron Spectroscopy ◽

Film Surface ◽

Grazing Incidence ◽

X Ray Diffraction ◽

X Ray ◽

Relative Composition ◽

Transmission Electron ◽

Deposited Film ◽

Deposited Films

We report the surface stoichiometry of Tix-CuyNz thin film as a function of film depth. Films are deposited by high power impulse (HiPIMS) and DC magnetron sputtering (DCMS). The composition of Ti, Cu, and N in the deposited film is investigated by X-ray photoelectron spectroscopy (XPS). At a larger depth, the relative composition of Cu and Ti in the film is increased compared to the surface. The amount of adventitious carbon which is present on the film surface strongly decreases with film depth. Deposited films also contain a significant amount of oxygen whose origin is not fully clear. Grazing incidence X-ray diffraction (GIXD) shows a Cu3N phase on the surface, while transmission electron microscopy (TEM) indicates a polycrystalline structure and the presence of a Ti3CuN phase.

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Synthesis of Ce1−xPdxO2−δ Solid Solution in Molten Nitrate

Catalysts ◽

10.3390/catal10060640 ◽

2020 ◽

Vol 10 (6) ◽

pp. 640

Author(s):

Hideaki Sasaki ◽

Keisuke Sakamoto ◽

Masami Mori ◽

Tatsuaki Sakamoto

Keyword(s):

Electron Microscopy ◽

Solid Solution ◽

Solid Solutions ◽

Photoelectron Spectroscopy ◽

Synthesis Method ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Co Precipitation ◽

Ionic States

CeO2-based solid solutions in which Pd partially substitutes for Ce attract considerable attention, owing to their high catalytic performances. In this study, the solid solution (Ce1−xPdxO2−δ) with a high Pd content (x ~ 0.2) was synthesized through co-precipitation under oxidative conditions using molten nitrate, and its structure and thermal decomposition were examined. The characteristics of the solid solution, such as the change in a lattice constant, inhibition of sintering, and ionic states, were examined using X-ray diffraction (XRD), scanning electron microscopy–energy-dispersive X-ray spectroscopy (SEM−EDS), transmission electron microscopy (TEM)−EDS, and X-ray photoelectron spectroscopy (XPS). The synthesis method proposed in this study appears suitable for the easy preparation of CeO2 solid solutions with a high Pd content.

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Study Structure and Properties of Nanocomposite Material Based on Unsaturated Polyester with Clay Modified by Poly(ethylene oxide)

Journal of Nanomaterials ◽

10.1155/2012/841813 ◽

2012 ◽

Vol 2012 ◽

pp. 1-5 ◽

Cited By ~ 8

Author(s):

Tran Duy Thanh ◽

Nguyen Dang Mao ◽

Nguyen Thi Kim Ngan ◽

Ha Thuc Chi Nhan ◽

Ha Thuc Huy ◽

...

Keyword(s):

Ethylene Oxide ◽

Polymer Matrix ◽

Unsaturated Polyester ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Poly Ethylene Oxide ◽

Hydrophobic Nature ◽

Poly Ethylene ◽

Alkyl Ammonium

In recent years, polymer clay nanocomposites have been attracting considerable interests in polymers science because of their advantages. There are many scientists who researched about this kind of material and demonstrated that when polymer matrix was added to little weight of clay, properties were enhanced considerably. Because clay is a hydrophilic substance so it is difficult to use as filler in polymer matrix having hydrophobic nature, so clay needs to be modified to become compatible with polymer. In this study, poly(ethylene oxide) was used as a new modifier for clay to replace some traditional ionic surfactants such as primary, secondary, tertiary, and quaternary alkyl ammonium or alkylphosphonium cations having the following disadvantages: disintegrate at high temperature, catalyze polymer degradation, and make nanoproducts colorific, and so forth. In order to evaluate modifying effect of poly(ethylene oxide), modified clay products were characterize d by X-ray spectrum. Then organoclay was used to prepare nanocomposite based on unsaturated polyester. Morphology and properties of nanocomposites were measure d by X-ray diffraction, transmission electron microscopy, tensile strength, and thermal stability. The results showed that clay galleries changed to intercalated state in the nanocomposites. Properties of nanocomposites were improved a lot when the loading of the organoclay was used at 1 phr.

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Characterization of columns grown during KrF laser micromachining of Al2O3–TiC ceramics

Journal of Materials Research ◽

10.1557/jmr.2003.0154 ◽

2003 ◽

Vol 18 (5) ◽

pp. 1123-1130 ◽

Cited By ~ 6

Author(s):

V. Oliveira ◽

R. Vilar

Keyword(s):

Electron Microscopy ◽

Photoelectron Spectroscopy ◽

Laser Pulses ◽

Formation Mechanisms ◽

X Ray ◽

Reducing Conditions ◽

Transmission Electron ◽

Column Formation ◽

Krf Laser

This paper aims to contribute to the understanding of column formation mechanisms in Al2O3–TiC ceramics micromachined using excimer lasers. Chemical and structural characterization of columns grown in Al2O3–TiC composite processed with 200 KrF laser pulses at 10 J/cm2 was carried out by scanning electron microscopy, transmission electron microscopy, x-ray photoelectron spectroscopy, and x-ray diffraction analysis. Fully developed columns consist of a core of unprocessed material surrounded by an outer layer of Al2TiO5, formed in oxidizing conditions, and an inner layer, formed in reducing conditions, composed of TiC and Al3Ti or an AlTi solid solution. Possible mechanisms of column formation are discussed.

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Green Synthesis of Feather-Shaped MoS2/CdS Photocatalyst for Effective Hydrogen Production

International Journal of Photoenergy ◽

10.1155/2013/247516 ◽

2013 ◽

Vol 2013 ◽

pp. 1-5 ◽

Cited By ~ 4

Author(s):

Yang Liu ◽

Hongtao Yu ◽

Xie Quan ◽

Shuo Chen

Keyword(s):

Electron Microscopy ◽

Hydrogen Production ◽

Photoelectron Spectroscopy ◽

Diffuse Reflectance ◽

Sulfur Source ◽

X Ray ◽

Transmission Electron ◽

Microscopy Images ◽

Effective Hydrogen ◽

Better Than

MoS2/CdS photocatalyst was fabricated by a hydrothermal method for H2production under visible light. This method used low toxic thiourea as a sulfur source and was carried out at 200°C. Thus, it was better than the traditional methods, which are based on an annealing process at relatively high temperature (above 400°C) using toxic H2S as reducing agent. Scanning electron microscopy and transmission electron microscopy images showed that the morphologies of MoS2/CdS samples were feather shaped and MoS2layer was on the surface of CdS. The X-ray photoelectron spectroscopy testified that the sample was composed of stoichiometric MoS2and CdS. The UV-vis diffuse reflectance spectra displayed that the loading of MoS2can enhance the optical absorption of MoS2/CdS. The photocatalytic activity of MoS2/CdS was evaluated by producing hydrogen. The hydrogen production rate on MoS2/CdS reached 192 μmol·h−1. This performance was stable during three repeated photocatalytic processes.

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