scholarly journals Dissolution and Interaction of Cellulose Carbamate in NaOH/ZnO Aqueous Solutions

Polymers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1092
Author(s):  
Yanhui Kang ◽  
Fangyu Wang ◽  
Zeming Zhang ◽  
Jinping Zhou
Keyword(s):  
Aqueous Solutions ◽  
Strong Interactions ◽  
Hydroxyl Groups ◽  
Scanning Calorimetry ◽  
Force Microscopy ◽  
Atomic Force ◽  
Transmission Electron ◽  
Cellulose Carbamate ◽  
Lower Temperature ◽  
The Stability

The dissolution and molecular interactions of cellulose carbamate (CC) in NaOH/ZnO aqueous solutions were studied using optical microscopy, differential scanning calorimetry (DSC), 1H NMR, dynamic light scattering (DLS), atomic force microscopy (AFM), transmission electron microscopy (TEM), and molecular dynamic simulation. The dissolution of CC in NaOH/ZnO aqueous solutions using the freezing–thawing method was an exothermic process, and the lower temperature was favorable for the dissolution of CC. ZnO dissolved in NaOH aqueous solutions with the formation of Zn(OH)42−, and no free Zn2+ ions existed in the solvents. NaOH/Na2Zn(OH)4 system formed strong interactions with the hydroxyl groups of CC to improve its solubility and the stability of CC solution. The results indicate that 7 wt% NaOH/1.6 wt% ZnO aqueous solution was the most appropriate solvent for the dissolution of CC. This work revealed the dissolution interaction of CC-NaOH/ZnO solutions, which is beneficial for the industrialization of the CarbaCell process.

Ball-Milling Graphite Used for Synthesis of Biocompatible Blue Luminescent Graphene Quantum Dots

2021 ◽  
Vol 6 (2) ◽  
Author(s):  
Zhou J ◽  
◽  
Dong Y ◽  
Ma Y ◽  
Zhang T ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Ball Milling ◽  
Graphene Quantum Dots ◽  
Raw Material ◽  
Hydroxyl Groups ◽  
High Quality ◽  
Widespread Application ◽  
Force Microscopy ◽  
Atomic Force ◽  
Transmission Electron

Graphene Quantum Dots (GQDs) have been prepared by oxidationhydrothermal reaction, using ball-milling graphite as the starting materials. The prepared GQDs are endowed with excellent luminescence properties, with the optimum emission of 320nm. Blue photoluminescent emitted from the GQDs under ultraviolet light. The GQDs are ~3nm in width and 0.5~2 nm in thickness, revealed by high-resolution transmission electron microscopy and atomic force microscopy. In addition, Fourier transform infrared spectrum evidences the existence of carbonyl and hydroxyl groups, meaning GQDs can be dispersed in water easily and used in cellar imaging, and blue area inside L929 cells were clearly observed under the fluorescence microscope. Both low price of raw material and simple prepared method contribute to the high quality GQDs widespread application in future.

Ta2O5-Incorporated WO3 Nanocomposite Film for Improved Electrochromic Performance in an Acidic Condition

2006 ◽  
Vol 6 (11) ◽  
pp. 3572-3576 ◽  
Author(s):  
Hee-Sang Shim ◽  
Hyo-Jin Ahn ◽  
Youn-Su Kim ◽  
Yung-Eun Sung ◽  
Won Bae Kim
Keyword(s):  
Surface Roughness ◽  
Photoelectron Spectroscopy ◽  
Potential Cycling ◽  
Force Microscopy ◽  
Atomic Force ◽  
Transmission Electron ◽  
Continuous Potential ◽  
Chemical States ◽  
The Stability

We report electrochromic and electrochemical properties of a WO3-Ta2O5 nanocomposite electrode that was fabricated from co-sputtering. Transmission electron microscopy (TEM)images of the WO3-Ta2O5 nanocomposite electrode revealed that morphology of the WO3 film was changed by incorporation of Ta2O5 nanoparticles, and their chemical states were confirmed to be W6+ and Ta5+ oxides from X-ray photoelectron spectroscopy (XPS). The introduction of Ta2O5 to the WO3 film played a role in alleviating surface roughness increase during continuous potential cycling; whereas the surface roughness of the WO3 film was increased from ca. 3.0 nm to ca. 13.4 nm after 400 cycles, the roughness increase on the WO3-Ta2O5 was significantly reduced to 4.2 nm after 400 cycles, as investigated by atomic force microscopy (AFM). This improvement of the stability by adding Ta2O5 may be responsible for the enhanced electrochemical and optical properties over long-term cycling with the WO3-Ta2O5 nanocomposite electrode.

Synthesis of polystyrene-grafted carbon nanocapsules

2007 ◽  
Vol 22 (1) ◽  
pp. 132-140 ◽  
Author(s):  
Hsuan-Ming Huang ◽  
Hung-Chieh Tsai ◽  
I-Chun Liu ◽  
Raymond Chien-Chao Tsiang
Keyword(s):  
Electron Microscopy ◽  
Molecular Weight ◽  
Polymeric Composite ◽  
Decomposition Temperature ◽  
Polymeric Composite Material ◽  
Scanning Calorimetry ◽  
Force Microscopy ◽  
Atomic Force ◽  
Transmission Electron ◽  
Carbon Nanocapsules

A novel polymeric composite material, polystyrene (PS)-grafted carbon nanocapsules (CNCs), has been prepared. sec-butyllithium was first used to introduce negative charges on CNCs, and these CNC carbanions acted then as initiators for anionic polymerization of styrene. Based on a weight loss at the decomposition temperature of the butyl groups, the quantity of the butyls attached to the CNC surface was determined as 1.18 wt%, corresponding to 0.25 mol% initiator per mol of carbon atom on the CNC surface. Furthermore, the decomposition temperature of butylated CNCs was lower than that of the pristine CNCs by nearly 200 °C. The polystyrene content in our PS-grafted CNC sample was approximately 20%, and the molecular weight of the grafted PS on the surface of CNCs was calculated as 1200 gmol−1. Compared with the molecular weight of the ungrafted PS, the molecular weight of grafted PS was lower, thus indicating rates of initiation and/or propagation for CNC-bound carbanions lower than those of the free sec-butyllithium. The PS-grafted CNCs had good dispersion in toluene, tetrahydrofuran, cyclohexane, and other common organic solvents in which polystyrene was dissolvable and thus indicated good compatibility when further blended with other styrenic polymers. The PS-grafted CNCs were characterized and examined by Fourier transform infrared, thermogravimetric analysis, atomic force microscopy, differential scanning calorimetry, ultraviolet-visible spectroscopy, Raman spectroscopy, scanning electron microscopy, and transmission electron microscopy. The electron microscopy images indicated that the PS-grafted CNCs were homogeneous composites containing uniform polymer/CNC ratios.

scholarly journals Characterization of the Spindle Morphology Nanomicelles Assembled from Sericin and Gelatin

2017 ◽  
Vol 2017 ◽  
pp. 1-9
Author(s):  
Xiaozhou Su ◽  
Lei Li ◽  
Weihan Huang
Keyword(s):  
Electron Microscopy ◽  
Protein Concentration ◽  
Scanning Calorimetry ◽  
Force Microscopy ◽  
Atomic Force ◽  
Transmission Electron ◽  
Ft Ir ◽  
And Storage ◽  
Ft Ir Spectroscopy

Complex nanomicelles were prepared by sericin and type A gelatin with molecular weight of 5789 Da and 128664 Da separately. The assembling conditions were as follows: mass ratio (sericin/gelatin) was 1 : 1, protein concentration was 0.5%, temperature was 35°C, and assembling time was 18 hours. Scanning electron microscopy (SEM), atomic force microscopy (AFM), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) spectroscopy, differential scanning calorimetry (DSC), and dynamic light scattering (DLS) were conducted to observe and characterize the complex nanomicelles. Results showed that the complex sericin/gelatin micelles was a kind of nanospindle micelles. The micelles had high electrochemical stability, thermal stability, antidilution stability, and storage stability.

Fabrication of Two-Dimensional PEDOT:PSS Nanosheets Through In Situ Formed Complexes

NANO ◽  
2015 ◽  
Vol 10 (01) ◽  
pp. 1550011 ◽  
Author(s):  
Kun Zhang ◽  
Shiren Wang
Keyword(s):  
In Situ Polymerization ◽  
Molecular Complexes ◽  
Water Soluble ◽  
Strong Interactions ◽  
Two Dimensional ◽  
Force Microscopy ◽  
Atomic Force ◽  
Ftir Characterization ◽  
Transmission Electron

This paper presents a simple and effective method to fabricate water-soluble two-dimensional (2D) conductive poly(3,4-ethylenedioxythiophene):poly (sodium 4-styrenesulfonate) (PEDOT:PSS) nanosheets. Linear PSS is water-soluble and exhibits a quasi 1D structure in the dilute solution. Addition of 3,4-ethylenedioxythiophene (EDOT) monomers into acidic solutions would form 2D molecular complexes due to charge attraction. In situ polymerization of the ethylenedioxythiophene monomers produces 2D poly EDOT nanosheets. Both transmission electron microscopy and atomic force microscopy characterizations have confirmed the 2D polymeric nanosheets. Further Fourier transform infrared (FTIR) characterization also validated that the 2D nanosheet is composed of EDOT-based units and Raman spectroscopy indicated the strong interactions between ethylenedioxythiophene units in the 2D nanostructures. The electrical conductivity is measured to as high as 551.58 S/m for the thin film of as-produced 2D PEDOT:PSS nanosheets.

MWCNT-reinforced polyarylene ether nitrile nanocomposites

2016 ◽  
Vol 29 (4) ◽  
pp. 441-449 ◽  
Author(s):  
Renbo Wei ◽  
Fei Jin ◽  
Cheng Long ◽  
Xiaobo Liu
Keyword(s):  
Hydroxyl Groups ◽  
Scanning Calorimetry ◽  
Force Microscopy ◽  
Polyarylene Ether Nitrile ◽  
Atomic Force ◽  
Multi Walled Carbon Nanotube ◽  
Solution Casting Method ◽  
Physical Performances ◽  
Mechanical Performances ◽  
Effect Of Surface

In this study, we investigated the effect of surface roughness of acidulated multi-walled carbon nanotube (MWCNT) on the physical performances of MWCNT/polyarylene ether nitrile (MWCNT/PEN) nanocomposites. Acidulated MWCNTs with different surface roughnesses were prepared by ultrasonicating and refluxing of MWCNTs in the mixture solvent of sulfuric acid/nitric acid and characterized by atomic force microscopy. With longer acidulating time, more and more oxygen functional groups including carboxyl and hydroxyl groups which result in the coarser surface of the obtained MWCNT, were generated. MWCNT/PEN composites were fabricated by using the solution-casting method with the acidulated MWCNTs and PEN. SEM observation showed that the acidulated MWCNTs are well-embedded in the polymer matrix without aggregation. differential scanning calorimetry and thermogravimetric analysis results showed that the incorporation of acidulated MWCNTs can improve the thermal behavior of the resulted polymer composites. The coarser the surface of the acidulated MWCNT, the better the mechanical performances of the obtained composites, while opposite results were observed for the dielectric properties of the nanocomposites. The dynamical rheological results showed that a better compatibility between the MWCNT and PEN is achieved when the coarser MWCNT is used.

DISPERSITY AND STABILITY MEASUREMENT OF FUNCTIONALIZED MULTIWALLED CARBON NANOTUBES IN ALCOHOLS

2008 ◽  
Vol 22 (25) ◽  
pp. 2493-2501 ◽  
Author(s):  
HUN-SIK KIM ◽  
MINSUNG KANG ◽  
WON-IL PARK ◽  
DON-YOUNG KIM ◽  
HYOUNG-JOON JIN
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Multiwalled Carbon Nanotubes ◽  
Photoelectron Spectroscopy ◽  
Multiwalled Carbon ◽  
Force Microscopy ◽  
Atomic Force ◽  
Transmission Electron ◽  
Stability Measurement ◽  
The Stability

Multiwalled carbon nanotubes (MWCNTs) were dispersed in various alcohols such as methanol, ethanol and isopropanol using ultrasonication. In order to disperse the MWCNTs in the alcohols, they were treated using a mixture of H 2 SO 4 and HNO 3 (3 : 1, vol/vol). The concentration of MWCNTs was approximately 0.03 wt.% and they formed a homogeneous dispersion in the alcohol solutions. The functional groups introduced on the surface of the MWCNTs during the acid treatment were characterized by Fourier transform-infrared spectroscopy and X-ray photoelectron spectroscopy. The dispersibility of the MWCNTs in the alcohols was characterized using atomic force microscopy, scanning electron microscopy and transmission electron microscopy. The stability of the MWCNT dispersions was also measured using a recently developed optical analyzer (Turbiscan).

scholarly journals Ultrasonic Preparation of PN For The Photodegradation of 17ß-Estradiol In Water And Biotoxicity Assessment Of E2 After Degradation

2021 ◽  
Author(s):  
Kun Meng ◽  
Ke-Fu Zhou ◽  
Nhat-Thien Nguyen ◽  
Bor-Yann Chen ◽  
Min Long ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Aqueous Solutions ◽  
Energy Dispersive Spectrometer ◽  
Degradation Efficiency ◽  
X Ray Diffraction ◽  
Force Microscopy ◽  
Synergistic Interactions ◽  
Atomic Force ◽  
Weight Content ◽  
Transmission Electron

Abstract This study prepared a novel Phosphorene (PN) and load it onto TiO2 to fabricated PN-TiO2, to effectively photo degrade the hydrophobic environmental hormone 17ß-estradiol in aqueous solutions. First, the corresponding characterization of prepared materials was implemented by myriads of methods (e.g, atomic force microscopy), transmission electron microscopy, scanning electron microscopy, energy dispersive spectrometer, X-ray diffraction and Raman spectroscopy. Next, the effect of the PN on the degradation efficiency was systematically investigated. Apparently, the doping of TiO2 by PN significantly enhanced its photocatalytic and adsorption properties with the addition of PN, compared to that in the absence of TiO2. That is the addition improved the adsorption capability of the composite. The optimal PN weight content was found to be 0.5%. However, the photo degradation efficiency gradually decreased when the PN content increased further. This optimal PN content directly suggested synergistic interactions upon the photo degrading efficiency. Compare to other PN-based photocatalysts mentioned in literature, this PN-based material owned striking advantages, such as higher energy efficiency, greater remove capacity, and superior cost-effectiveness. Further, biotoxicity of the water after treatment decreased was evident by observing the development of zebrafish embryos. In conclusion, the prepared PN-based materials exhibited promising photocatalytic capabilities for removal and biotoxicity reduction of 17ß-estradiol in aqueous solutions.

scholarly journals Hydrophobic Epoxy Caged Silsesquioxane Film (EP-POSS): Synthesis and Performance Characterization

Nanomaterials ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 472
Author(s):  
Yanhong Fang ◽  
Ping Wang ◽  
Lifang Sun ◽  
Linhong Wang
Keyword(s):  
Electron Microscopy ◽  
Photoelectron Spectroscopy ◽  
Mechanical Performance ◽  
Solar Panels ◽  
Scanning Calorimetry ◽  
Force Microscopy ◽  
Atomic Force ◽  
Transmission Electron ◽  
Surface Micromorphology ◽  
And Performance

Hydrophobic films are widely used in aerospace, military weapons, high-rise building exterior glass, and non-destructive pipeline transportation due to their antifouling and self-cleaning properties. This paper details the successful preparation of hydrophobic epoxy caged sesquioxane (EP-POSS) via two steps of simple organic synthesis, along with studies on the effects of viscosity and reaction time on the reaction. Interestingly, the EP-POSS presented a large contact angle of 125°, indicating its excellent hydrophobicity. The surface micromorphology was observed via FE-SEM (field emission scanning electron microscopy), transmission electron microscopy (TEM), and atomic force microscopy (AFM), and the structural composition and elemental contents were analyzed via X-ray photoelectron spectroscopy (XPS) and energy-dispersive spectrometry (EDS). Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) tests showed that EP-POSS had excellent thermal properties, and the first degradation reaction occurred at 354 °C. The mechanical performance and abrasion resistance results demonstrated that EP-POSS could be used in solar panels.

scholarly journals Synergetic Improvement of Stability and Conductivity of Hybrid Composites formed by PEDOT:PSS and SnO Nanoparticles

Molecules ◽  
2020 ◽  
Vol 25 (3) ◽  
pp. 695 ◽  
Author(s):  
Antonio Vázquez-López ◽  
Anisa Yaseen ◽  
David Maestre ◽  
Julio Ramírez-Castellanos ◽  
Erik S. Marstein ◽  
...  
Keyword(s):  
Hybrid Composites ◽  
X Ray Diffraction ◽  
Laser Illumination ◽  
Force Microscopy ◽  
Atomic Force ◽  
Transmission Electron ◽  
Hall Effect Measurements ◽  
Laser Sources ◽  
The Stability ◽  
Composite Study

In this work, layered hybrid composites formed by tin oxide (SnO) nanoparticles synthesized by hydrolysis and poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) have been analyzed. Prior to the composite study, both SnO and PEDOT:PSS counterparts were characterized by diverse techniques, such as X-ray diffraction (XRD), Raman spectroscopy, transmission electron microscopy (TEM), photoluminescence (PL), atomic force microscopy (AFM), optical absorption and Hall effect measurements. Special attention was given to the study of the stability of the polymer under laser illumination, as well as the analysis of the SnO to SnO2 oxidation assisted by laser irradiation, for which different laser sources and neutral filters were employed. Synergetic effects were observed in the hybrid composite, as the addition of SnO nanoparticles improves the stability and electrical conductivity of the polymer, while the polymeric matrix in which the nanoparticles are embedded hinders formation of SnO2. Finally, the Si passivation behavior of the hybrid composites was studied.

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