Effect of Magnetic Field on the Electropolymerization and Corrosion Properties of Polyaniline (PANI) Film

2012 ◽  
Vol 472-475 ◽  
pp. 198-205 ◽  
Author(s):  
Chao Fang Dong ◽  
Yang Yang ◽  
Hong Luo ◽  
Kui Xiao ◽  
Xiao Gang Li

The polyaniline have been prepared in the absence and presence of magnetic field by the technique of cyclic voltammetry (CV) on 304-stainless steel electrode in H2SO4 aqueous solution of aniline (Ani). The influence of magnetic field on electropolymerization of PANI was investigated by electrochemical properties, FT-IR spectra, X-ray diffraction (XRD) and microstructure. The results indicate that the effect of magnetic field on the polyaniline is positive.

2013 ◽  
Vol 838-841 ◽  
pp. 2306-2309
Author(s):  
Guang Hua Wang ◽  
Kun Chen ◽  
Wen Bing Li ◽  
Dong Wan ◽  
Qin Hu ◽  
...  

Magnetic modified organobentonite (Fe3O4/CTAB–Bent) was synthesized by chemical co-precipitation method in which CTAB–Bent was firstly achieved via ion–exchange.The composite materials have been characterized by powder X–ray diffraction (XRD), Fourier transform infrared spectroscopy (FT–IR) and Scanning electron microscopy (SEM) . The results revealed that basal spacing of bentonite was increased through organic modification and the Fe3O4 particles synthesized which covering the surfaces of bentonite .Compared with natural bentonite, the adsorption capacity of Fe3O4/CTAB–Bent for Orange II was greatly enhanced and can be easily separated from the reaction medium by an external magnetic field after the treatment.


2020 ◽  
Vol 38 (9-10) ◽  
pp. 483-501
Author(s):  
Nguyen Thi Huong ◽  
Nguyen Ngoc Son ◽  
Vo Hoang Phuong ◽  
Cong Tien Dung ◽  
Pham Thi Mai Huong ◽  
...  

The Fe3O4/Talc nanocomposite was synthesized by the coprecipitation-ultrasonication method. The reaction was carried out under a inert gas environment. The nanoparticles were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), fourier-transform infrared spectroscopy (FT-IR) and vibrating sample magnetometry techniques (VSM), the surface area of the nanoparticles was determined to be 77.92 m2/g by Brunauer-Emmett-Teller method (BET). The kinetic data showed that the adsorption process fitted with the pseudo-second order model. Batch experiments were carried out to determine the adsorption kinetics and mechanisms of Cr(VI) by Fe3O4/Talc nanocomposite. The adsorption process was found to be highly pH-dependent, which made the material selectively adsorb these metals from aqueous solution. The isotherms of adsorption were also studied using Langmuir and Freundlich equations in linear forms. It is found that the Langmuir equation showed better linear correlation with the experimental data than the Freundlich. The thermodynamics of Cr(VI) adsorption onto the Fe3O4/Talc nanocomposite indicated that the adsorption was exothermic. The reusability study has proven that Fe3O4/Talc nanocomposite can be employed as a low-cost and easy to separate.


2017 ◽  
Vol 727 ◽  
pp. 859-865 ◽  
Author(s):  
Yi Wei Zheng ◽  
Wen Wen Tao ◽  
Gui Fang Zhang ◽  
Chao Lv ◽  
Yi Ping Zhao ◽  
...  

Polyacrylic acid/attapulgite (PAA/ATP) composite hydrogels used for removal of heavy metal ions from aqueous solution was synthesized via radical polymerization with acrylic acid (AA) and attapulgite (ATP) modified by hydrochloric acid as adsorbent. Chemical composition of the modified ATP was characterized by Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) and the morphology of the PAA/ATP hydrogels was characterized by scanning electron microscope (SEM), respectively. The swelling ratio, pH-sensitivity and adsorption performance of Ni (II) ions of the composite hydrogels were studied. The results showed the swelling ratio of the PAA/ATP composite hydrogels was higher than that of PAA hydrogels and the composite hydrogels displayed sensitivity to pH values with a sharp increase of swelling ratio when the pH values increased from 4 to 6. Comparing with PAA hydrogels, the composite hydrogels obtained a larger adsorption capacity of Ni (II) ions, the average adsorption capacity could reach 72.8 mg/g and adsorption ratio could reach 84%.


2018 ◽  
Vol 2018 ◽  
pp. 1-6 ◽  
Author(s):  
A. Morfin-Gutiérrez ◽  
H. Iván Meléndez-Ortiz ◽  
B. A. Puente-Urbina ◽  
L. A. García-Cerda

In this study, the synthesis, characterization, and application of poly(N-vinylcaprolactam)-grafted magnetite nanocomposites for magnetic hyperthermia are reported. Superparamagnetic magnetite nanoparticles (MagNPs) with sizes in the range of 10–16 nm were synthesized by the coprecipitation method and then functionalized with vinyltrimethoxysilane (VTMS). MagNPs-VTMS coated with poly(N-vinylcaprolactam) (PNVCL) were prepared by free radical polymerization. The obtained materials were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), vibration sample magnetometry (VSM), and Fourier transform infrared spectroscopy (FT-IR). The heating ability was evaluated under a magnetic field using a solid state induction heating equipment at 10.2 kA/m and 362 kHz. The MagNPs-PNVCL nanocomposites showed a behavior close to superparamagnetic materials, which is appropriated for magnetic hyperthermia treatment; in concentrations of 8 mg/mL, they were able to heat up, increasing the temperature up to 42°C in a period of time lower than 10 minutes.


Polymers ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 960 ◽  
Author(s):  
Thi Hang Nguyen ◽  
Thi Thuy Linh Nguyen ◽  
Tien Duc Pham ◽  
Thanh Son Le

In the present study, we investigated the removal of an emerging pesticide lindane from aqueous solution using synthesized aluminum hydroxide Al(OH)3 (bayerite) nanomaterials with surface modification by an anionic surfactant sodium dodecyl sulfate (SDS). The Al(OH)3 nanoparticles were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET) and zeta potential. The lindane removal using SDS-modified nano-aluminum hydroxide nanoparticles (SMNAH) achieved removal of up to 93.68%, which was 3.3 times higher than that of nano-aluminum hydroxide nanoparticles. The adsorptive removal conditions were studied and found to have an adsorption time of 60 min, a pH of 6, an adsorbent dosage of 25 mg/mL and an ionic strength of 10 mM NaCl. After reusing four times, the removal efficiency of lindane using SMNAH still reached 75%. Two-step adsorption can fit adsorption isotherms of lindane onto SMNAH at two salt concentrations. On the basis of the change in zeta potential, surface functional groups and adsorption isotherms, we suggest that the formation of a bilayer micelle induced the removal of lindane.


Coatings ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 653
Author(s):  
Francisco R. Rangel-Olivares ◽  
Elsa M. Arce-Estrada ◽  
Román Cabrera-Sierra

Polymer nanocomposites of polyaniline (PANI)-based metal oxides (SiO2, CeO2, and TiO2A) were synthesized by in situ chemical oxidative polymerization by rapid mixing in a hydrochloric acid medium to evaluate and compare their performance as anti-corrosion coatings on commercial 1018 steel in a 3.5% NaCl medium. The anti-corrosion coatings were developed by dispersing synthesized nanocomposites on an alkydalic resin (AR) for their subsequent electrochemical characterization. X-ray diffraction (XRD) analyses show that PANI has a certain degree of crystallinity in its structure. The incorporation of metal oxide (MO) nanoparticles (NPs) into the polymer matrix was confirmed by scanning electron microscopy and energy-dispersive X-ray spectroscopy (SEM-EDS) analyses, while the interaction of nanoparticles with PANI was proven by Fourier transform infrared (FT-IR) and ultraviolet-visible (UV-vis). Thermogravimetric analysis (TGA) reveals that nanoparticles infer greater resistance to the thermal decomposition of PANI. Finally, the use of open circuit potential (OCP) study, Tafel curves, and electrochemical impedance spectroscopy (EIS) showed that coatings made with TiO2A NPs exhibit the best anti-corrosion properties as compared to those synthesized with SiO2 and CeO2 NPs.


Polymers ◽  
2018 ◽  
Vol 10 (9) ◽  
pp. 1042 ◽  
Author(s):  
Yohan Kim ◽  
Daham Jeong ◽  
Kyeong Park ◽  
Jae-Hyuk Yu ◽  
Seunho Jung

Benzoyl and stearoyl acid grafted cellulose were synthesized by a simple chemical grafting method. Using these as chemical adsorbents, polycyclic aromatic hydrocarbons (PAHs), like pyrene and phenanthrene, were effectively removed from aqueous solution. The structural and morphological properties of the synthesized adsorbents were determined through X-ray diffraction analysis (XRD), thermal gravimetric analysis (TGA), Fourier transform infrared (FT-IR), FE-SEM, and NMR analyses. Through this method, it was confirmed that benzoyl and stearoyl acid were successfully grafted onto the surface of cellulose. The 5 mg of stearoyl grafted cellulose (St–Cell) remove 96.94% pyrene and 97.61% phenanthrene as compared to unmodified cellulose, which adsorbed 1.46% pyrene and 2.99% phenanthrene from 0.08 ppm pyrene and 0.8 ppm phenanthrene aqueous solution, suggesting that those results show a very efficient adsorption performance as compared to the unmodified cellulose.


2018 ◽  
Vol 78 (12) ◽  
pp. 2469-2480
Author(s):  
Avat Ghasemi ◽  
Mahmoud Reza Sohrabi ◽  
Fereshteh Motiee

Abstract A new sawdust/magnetite nanoparticles/polyethyleneimine (SD/MNP/PEI) nanocomposite was synthesized by grafting polyethyleneimine (PEI) to magnetic sawdust. Features of SD/MNP/PEI were characterized using Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD), vibrating sample magnetometer (VSM) and scanning electron microscopy (SEM). SD/MNP/PEI was used as an adsorbent for the removal of lead (Pb (II)) from aqueous solution. The effects of independent variables including pH of solution, adsorbent dose and contact time were performed and adsorption isotherms were obtained. Experimental results show that priority effective variables were pH and the amount of nanocomposite, and it was found that the sorption capacity increases with the increasing phase contact time. The adsorption process followed the Langmuir adsorption isotherm. Although SD and SD/MNP do not show a high affinity for the adsorption of Pb (II) in aqueous media, polyethyleneimine cross-linked on SD/MNP showed 40 and 66% increases, respectively, in the adsorption of Pb (II) compared to the SD and SD/MNP. It was found that SD/MNP/PEI removes more efficiently lead ions from aqueous solutions than the SD, SD/MNP. Desorption of the lead from the SD/MNP/PEI was conducted. It was proved that SD/MNP/PEI has excellent properties and can be used as a sorbent of multi-use.


2016 ◽  
Vol 30 (17) ◽  
pp. 1650094 ◽  
Author(s):  
Raid A. Ismail ◽  
Ghassan M. Sulaiman ◽  
Safa A. Abdulrahman

We have studied the effect of applying an external magnetic field on the characteristics of iron oxide (IO) nanoparticles (NPs) synthesized by pulsed laser ablation in dimethylformamide (DMF). The NPs synthesized with and without applying of magnetic field were characterized by Fourier transformation infrared spectroscopy (FT-IR), UV–Vis absorption, scanning electron microscope (SEM), atomic force microscope (AFM), and X-ray diffraction (XRD). SEM results confirmed that the particle size was decreased after applying magnetic field.


2013 ◽  
Vol 67 (2) ◽  
pp. 306-310 ◽  
Author(s):  
Wen Ding ◽  
Shen-yong Zhai ◽  
Jun-tao liu ◽  
Rou Wang ◽  
Rong Li

Dialdehyde 8-aminoquinoline starch (DASQA) was synthesized by the reaction of dialdehyde starch (DAS) and 8-aminoquinoline and was used to adsorb various ions from aqueous solution. DASQA was characterized by Fourier transform infrared (FT-IR) spectra, thermogravimetric analysis, X-ray diffraction analysis. The adsorption properties of the polymer for Pb2+, Cu2+, Cd2+, Ni2+, and Zn2+ were investigated. The result of the experiment reveals that the adsorption for Cd2+ and Zn2+were approximately 2.51 mmol/g, 2.17 mmol/g, followed by Pb2+ 1.93 mmol/g, Ni2+ 1.66 mmol/g, Cu2+ 1.19 mmol/g. Furthermore, the kinetic experiments indicated that the adsorption of DASQA for the above metal ions achieved equilibrium within 2 h. Therefore, DASQA is an effective adsorbent for the removal of different heavy metal ions from industrial waste solutions.


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