Gum Arabic Nanoparticles as Green Corrosion Inhibitor for Reinforced Concrete Exposed to Carbon Dioxide Environment

The inhibiting effect of Gum Arabic-nanoparticles (GA-NPs) to control the corrosion of reinforced concrete that exposed to carbon dioxide environment for 180 days has been investigated. The steel reinforcement of concrete in presence and absence of GA-NPs were examined using various standard techniques. The physical/surface changes of steel reinforcement was screened using weight loss measurement, electrochemical impedance spectroscopy (EIS), atomic force microscopy and scanning electron microscopy (SEM). In addition, the carbonation resistance of concrete as well screened using visual inspection (carbonation depth), concrete alkalinity (pH), thermogravimetric analysis (TGA), SEM, energy-dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD). The GA-NPs inhibitor size was also confirmed by transmission electron microscopy (TEM). The results obtained revealed that incorporation of 3% GA-NPs inhibitor into concrete inhibited the corrosion process via adsorption of inhibitor molecules over the steel reinforcement surface resulting of a protective layer formation. Thus, the inhibition efficiency was found to increase up-to 94.5% with decreasing corrosion rate up-to 0.57 × 10−3 mm/year. Besides, the results also make evident the presence of GA-NPs inhibitor, ascribed to the consumption of calcium hydroxide, and reduced the Ca/Si to 3.72% and 0.69% respectively. Hence, C-S-H gel was developed and pH was increased by 9.27% and 12.5, respectively. It can be concluded that green GA-NPs have significant corrosion inhibition potential and improve the carbonation resistance of the concrete matrix to acquire durable reinforced concrete structures.

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Few-Layered MoS2 Nanostructures for Highly Efficient Visible Light Photocatalysis

NANO ◽

10.1142/s1793292016501149 ◽

2016 ◽

Vol 11 (10) ◽

pp. 1650114 ◽

Cited By ~ 5

Author(s):

Dan Li ◽

Jianwei Li ◽

Caiqin Han ◽

Xinsheng Zhao ◽

Haipeng Chu ◽

...

Keyword(s):

Electron Microscopy ◽

Photocatalytic Activity ◽

Visible Light ◽

Electrochemical Impedance ◽

X Ray Diffraction ◽

Electron Hole ◽

Electrochemical Impedance Spectra ◽

X Ray ◽

Transmission Electron ◽

Electron Hole Pair

Few-layered MoS2 nanostructures were successfully synthesized by a simple hydrothermal method without the addition of any catalysts or surfactants. Their morphology, structure and photocatalytic activity were characterized by X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, transmission electron microscopy, electrochemical impedance spectra and UV-Vis absorption spectroscopy, respectively. These results show that the MoS2 nanostructures synthesized at 180[Formula: see text]C exhibit an optimal visible light photocatalytic activity (99%) in the degradation of Rhodamine B owing to the relatively easier adsorption of pollutants, higher visible light absorption and lower electron–hole pair recombination.

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Amorphous Ni x Co y P-supported TiO2 nanotube arrays as an efficient hydrogen evolution reaction electrocatalyst in acidic solution

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.10.6 ◽

2019 ◽

Vol 10 ◽

pp. 62-70 ◽

Cited By ~ 5

Author(s):

Yong Li ◽

Peng Yang ◽

Bin Wang ◽

Zhongqing Liu

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Hydrogen Evolution ◽

Hydrogen Evolution Reaction ◽

Photoelectron Spectroscopy ◽

Electrochemical Impedance ◽

Nanotube Arrays ◽

Active Surface Area ◽

X Ray ◽

Transmission Electron

Bimetallic phosphides have been attracting increasing attention due to their synergistic effect for improving the hydrogen evolution reaction as compared to monometallic phosphides. In this work, NiCoP modified hybrid electrodes were fabricated by a one-step electrodeposition process with TiO2 nanotube arrays (TNAs) as a carrier. X-ray diffraction, transmission electron microscopy, UV–vis diffuse reflection spectroscopy, X-ray photoelectron spectroscopy and scanning transmission electron microscopy/energy-dispersive X-ray spectroscopy were used to characterize the physiochemical properties of the samples. The electrochemical performance was investigated by cyclic voltammetry, linear sweep voltammetry, and electrochemical impedance spectroscopy. We show that after incorporating Co into Ni–P, the resulting Ni x Co y P/TNAs present enhanced electrocatalytic activity due to the improved electron transfer and increased electrochemically active surface area (ECSA). In 0.5 mol L−1 H2SO4 electrolyte, the Ni x Co y P/TNAs (x = 3.84, y = 0.78) demonstrated an ECSA value of 52.1 mF cm−2, which is 3.8 times that of Ni–P/TNAs (13.7 mF cm−2). In a two-electrode system with a Pt sheet as the anode, the Ni x Co y P/TNAs presented a bath voltage of 1.92 V at 100 mA cm−2, which is an improvment of 79% over that of 1.07 V at 10 mA cm−2.

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Laccase Biosensor Based on Ag-Doped TiO2 Nanoparticles on CuCNFs for the Determination of Hydroquinone

NANO ◽

10.1142/s1793292016501320 ◽

2016 ◽

Vol 11 (12) ◽

pp. 1650132 ◽

Cited By ~ 2

Author(s):

Jie Yang ◽

Dawei Li ◽

Zengyuan Pang ◽

Qufu Wei

Keyword(s):

Electron Microscopy ◽

Storage Stability ◽

Electrochemical Impedance ◽

The Novel ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

New Material ◽

And Storage

A novel nanomaterial composed of copper and carbon nanofibers (CuCNFs) decorated with Ag-doped TiO2 (Ag–TiO[Formula: see text] nanoparticles was prepared through electrospinning, carbonization and solvothermal treatment. The composites were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and electrochemical impedance spectroscopy (EIS). The obtained composites were mixed with laccase and Nafion to construct novel hydroquinone biosensor. The electrochemical behavior of the novel biosensor was studied using cyclic voltammetry (CV) and chronoamperometry. The results demonstrated that the biosensor possessed a wide detection linear range (1.20–176.50[Formula: see text][Formula: see text]M), a good selectivity, repeatability, reproducibility and storage stability. This work provides a new material to design more efficient laccase (Lac) based biosensor for hydroquinone detection.

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Sensitive and Selective Electrochemical Detection of Epirubicin as Anticancer Drug Based on Nickel Ferrite Decorated with Gold Nanoparticles

Micromachines ◽

10.3390/mi12111334 ◽

2021 ◽

Vol 12 (11) ◽

pp. 1334

Author(s):

Mohammad Mehmandoust ◽

Nevin Erk ◽

Ceren Karaman ◽

Fatemeh Karimi ◽

Sadegh Salmanpour

Keyword(s):

Electron Microscopy ◽

Gold Nanoparticles ◽

Nickel Ferrite ◽

Electrochemical Impedance ◽

Limit Of Detection ◽

Differential Pulse ◽

X Ray ◽

Transmission Electron ◽

The Stability ◽

Electrochemical Electrode

The accurate and precise monitoring of epirubicin (EPR), one of the most widely used anticancer drugs, is significant for human and environmental health. In this context, we developed a highly sensitive electrochemical electrode for EPR detection based on nickel ferrite decorated with gold nanoparticles (Au@NiFe2O4) on the screen-printed electrode (SPE). Various spectral characteristic methods such as Fourier transform infrared spectra (FT-IR), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), ultraviolet-visible spectroscopy (UV-Vis), energy-dispersive X-ray spectroscopy (EDX) and electrochemical impedance spectroscopy (EIS) were used to investigate the surface morphology and structure of the synthesized Au@NiFe2O4 nanocomposite. The novel decorated electrode exhibited a high electrocatalytic activity toward the electrooxidation of EPR, and a nanomolar limit of detection (5.3 nM) was estimated using differential pulse voltammetry (DPV) with linear concentration ranges from 0.01 to 0.7 and 0.7 to 3.6 µM. The stability, selectivity, repeatability reproducibility and reusability, with a very low electrode response detection limit, make it very appropriate for determining trace amounts of EPR in pharmaceutical and clinical preparations.

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CuWO4 Nanoparticles: Investigation of Dielectric, Electrochemical Behaviour and Photodegradation of Pharmaceutical Waste

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2019.16601 ◽

2019 ◽

Vol 19 (11) ◽

pp. 7026-7034 ◽

Cited By ~ 1

Author(s):

M. Thiruppathi ◽

M. Vahini ◽

P. Devendran ◽

M. Arunpandian ◽

K. Selvakumar ◽

...

Keyword(s):

Electron Microscopy ◽

Room Temperature ◽

Electrochemical Impedance ◽

Electrochemical Behaviour ◽

Diclofenac Sodium ◽

X Ray Diffraction ◽

Sem Images ◽

X Ray ◽

Transmission Electron ◽

Pharmaceutical Waste

The hydrothermally synthesized CuWO4 nanoparticles (NPs) were characterized with different analysis such as X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), High Resolution Transmission Electron Microscopy (HRTEM), Energy Dispersive X-ray Spectroscopy (EDX), Cyclic Voltammetry (CV), UV-Visible and Photoluminescence (PL) analysis. The prepared CuWO4 NPs were examined with Electrochemical Impedance Spectroscopy (EIS). SEM images show that CuWO4 NPs are highly spherical shaped morphology and porous in nature. The optical band gap of prepared CuWO4 NPs is found to be 2.12 eV. Photodegradation of diclofenac sodium (DFS) (medical waste) in the aqueous medium with CuWO4 NPs under visible light irradiation shows 98% degradation. The CuWO4 NPs was stable up to 5th cycle it can be used as a reusable photocatalyst for the DFS degradation. The electrical conductivity and dielectric properties of the CuWO4 NPs at room temperature is analyzed by EIS studies. The bulk conductivity value of the prepared nanoparticles is 1.477×10-5 S/cm at room temperature. The conductivity of CuWO4 NPs is found to be due to electrons movement. The CuWO4 NPs shows higher photocatalytic and electrocatalytic activity for decomposition of DFS and methanol electro-oxidation in alkaline medium respectively.

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Investigation of corrosion behavior on plastically deformed aa 7075 t651 by shot peening process

Surface Topography Metrology and Properties ◽

10.1088/2051-672x/ac34c0 ◽

2021 ◽

Author(s):

Abeens M ◽

R Murugananthan

Keyword(s):

Electron Microscopy ◽

Corrosion Resistance ◽

Dislocation Density ◽

Aluminium Alloy ◽

Electrochemical Impedance ◽

Corrosion Behaviour ◽

X Ray ◽

Transmission Electron ◽

Aa 7075 ◽

Micro Structures

Abstract As AA 7075 T651 comprehensively is used in the marine naval vessels, the factor of corrosion performance always plays a significant role. In this work, an investigation is carried out to study the effect of corrosion behaviour of shot peened AA 7075 T651 in 3.5% solution. From the potentiodynamic polarization study, a 27.72% decrease is ascertained in the Icorr in shot peened specimen in correlation to unpeened aluminium alloy. A drop in Icorr from 1.883 to 1.480 mA/cm2 in shot peened specimen, indicates enhanced pitting corrosion resistance. An electrochemical impedance spectroscopy reveals a surge in the oxide layer formation on the peened surface aiding the drop in corrosion rate. Resistance to pit formations and improvement in oxygen deposition in the peened specimen is observed availing a Scanning Electron Microscopy (SEM) and Energy Dispersive X-Ray analysis (EDX). The micro structures of the peened and unpeened specimen are captured using optical microscopy and Transmission electron microscopy (TEM). Micro-strain, dislocation density is also calculated from the X- ray diffraction analysis (XRD), in which grain size reduces by 28.07%, dislocation density surges by 38.65% and micro strain increases by 21.95% in peened specimen in correlation to unpeened AA 7075 T651, resulting in a surge in corrosion resistance by 27.92% in the peened specimen in correlation to unpeened aluminium alloy.

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One-pot synthesis of cellulose/MoS2 composite for efficient visible-light photocatalytic reduction of Cr(VI)

BioResources ◽

10.15376/biores.14.3.6114-6133 ◽

2019 ◽

Vol 14 (3) ◽

pp. 6114-6133

Author(s):

Chunxiang Lin ◽

Yushi Liu ◽

Qiaoquan Su ◽

Yifan Liu ◽

Yuancai Lv ◽

...

Keyword(s):

Electron Microscopy ◽

Electrochemical Impedance ◽

Photocatalytic Reduction ◽

X Ray Diffraction ◽

One Pot ◽

Simultaneous Reduction ◽

X Ray ◽

Transmission Electron ◽

Reduction Efficiency ◽

Hole Scavenger

An effective cellulose/MoS2 (Ce/MoS2) composite was synthesized via a one-pot microwave-assisted ionic liquid method for the photocatalytic reduction of toxic Cr(VI). Effects of ionic liquids (ILs) on the MoS2 nanostructure were considered, and the obtained composite was characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectrometry (XPS), and electrochemical impedance spectroscopy (EIS). The results indicated that the MoS2 nanoplates were anchored and dispersed on the surface of the cellulose. Compared with the pristine MoS2, the support of the cellulose greatly enhanced the photocatalytic reduction efficiency of Cr(VI) ions in solution, from 65.9% to nearly 100%. The reduction mechanism was considered, and the results implied that the simultaneous reduction of Cr(VI) during the initial dark adsorption process was observed due to the effect of citric acid as a hole scavenger. Finally, regeneration tests revealed that the Ce/MoS2 composite could be recycled and reused.

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A low-cost, low-density, and corrosion resistant AlFeMnSi compositionally complex alloy

npj Materials Degradation ◽

10.1038/s41529-021-00158-5 ◽

2021 ◽

Vol 5 (1) ◽

Author(s):

S. P. O’Brien ◽

J. Christudasjustus ◽

L. Esteves ◽

S. Vijayan ◽

J. R. Jinschek ◽

...

Keyword(s):

Electron Microscopy ◽

Photoelectron Spectroscopy ◽

Electrochemical Impedance ◽

Surface Film ◽

Low Cost ◽

Incongruent Dissolution ◽

Complex Alloy ◽

X Ray ◽

Transmission Electron ◽

Scanning Transmission

AbstractA compositionally complex alloy was designed, consisting of equiatomic concentrations of four low-cost commodity elements (Al, Fe, Mn, and Si). The alloy was characterized using scanning electron microscopy and energy-dispersive X-ray spectroscopy. The corrosion of the AlFeMnSi alloy, as evaluated using potentiodynamic polarization tests and electrochemical impedance spectroscopy in 0.6 M NaCl solution, was comparable with that of stainless steel (SS) 304L. Detailed X-ray photoelectron spectroscopy analysis was carried out, including the determination of high-resolution spectra and surface sputtering. In addition, scanning transmission electron microscopy was also used to study the surface film(s) developed after constant immersion. The AlFeMnSi alloy exhibited a unique form of ‘passivity’ that arises from the development of a silicon-rich surface film from dynamic incongruent dissolution.

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Evolution of Waste Iron Rust into α-Fe2O3/CNF and α-Fe2O3/PANI Composites as an Efficient Positive Electrode for Sustainable Hybrid Super-capacitor

10.21203/rs.3.rs-202258/v1 ◽

2021 ◽

Author(s):

Darpan Vijaykumar Bhuse ◽

Vijaykumar M Bhuse ◽

Ramdas G Atram ◽

Rounak R Atram ◽

Subhash B Kondawar

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Active Sites ◽

Electrode Materials ◽

Electrochemical Impedance ◽

Potential Candidate ◽

Hybrid Supercapacitor ◽

Supercapacitor Electrode ◽

X Ray ◽

Transmission Electron

Abstract A green and sustainable approach to recycle the waste iron rust into a valuable α modification of Fe2O3 via simple grinding and calcination for application in hybrid supercapacitor is reported. The α-Fe2O3 was coupled with conducting polymer carbon nanofibers (CNF) and Poly aniline (PANI) to form composite hybrid supercapacitor electrode materials. The conventional hydrothermal, electro-spinning processes were used to prepare composites. X-ray diffraction, Transmission Electron Microscopy (TEM), High Resolution Transmission Electron Microscopy (HRTEM), Selected Area Electron Diffraction (SAED), Scanning Electron Microscopy and Energy Dispersive X-Ray spectroscopy were used to study the structural, morphological and compositional properties of as synthesised α-Fe2O3 and its composites with CNF and PANI. The α-Fe2O3/CNF and α-Fe2O3/PANI composites coated on carbon rod were used as electrodes in a three-electrode system to study Electrochemical Impedance Spectroscopy, Cyclic Voltammetry and Galvanostatic Charge-Discharge in 1M H2SO4. It is observed that α-Fe2O3/PANI exhibit higher response as against α-Fe2O3/CNF with respect to specific capacitance; 192.29 Fg-1 (88.88 Fg-1), energy density; 11.28 WhKg-1 (3.084 WhKg-1) power density; 162.44Wkg-1 (69.39 Wkg-1) with capacitance retention of 80% (75%). The heavy dispersion of α-Fe2O3 over long CNF and PANI fibres with intimate contact resulted in abundant active sites for electrochemical reactions leading to obtained result. The rust derived α-Fe2O3 with PANI offer excellent stability to act as potential candidate for sustainable hybrid supercapacitor application.

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Carbon Dioxide – Dilated Block Copolymer Templates for Nanostructured Materials

MRS Proceedings ◽

10.1557/proc-584-169 ◽

1999 ◽

Vol 584 ◽

Cited By ~ 7

Author(s):

Garth D. Brown ◽

James J. Watkins

Keyword(s):

Electron Microscopy ◽

Carbon Dioxide ◽

Transmission Electron Microscopy ◽

Organometallic Compounds ◽

X Ray ◽

X Ray Scattering ◽

Transmission Electron ◽

Metal Precursors ◽

Polymer Semiconductor ◽

Polymer Metal

AbstractPeriodic polymer/metal (Pt or Ag) and polymer/semiconductor (PbS) nanocomposites are prepared using block copolymers dilated with carbon dioxide (CO2) as templates. Specifically, organometallic compounds (metal precursors) are dissolved into supercritical CO2 and infused into polystyrene-block-poly(acrylic acid) or polystyrene-block-poly(vinylpyridine) copolymers. Upon infusion, the acid or pyridine block selectively binds the metal precursor. The excess is removed from the polystyrene phase by subsequent CO2 extraction. Reduction of the bound organometallic with hydrogen or hydrogen sulfide yields the desired metal or semiconductor clusters, which are confined to the precursor-binding domain and remain positioned on the copolymer lattice. The composites are characterized by transmission electron microscopy, x-ray scattering and electron diffraction.

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