In this study, mesoporous silica/iron oxide nanocomposite(MCM-FeO) was synthesized via hydrothermal technique. The chemical synthesis of MCM-FeOnanocomposite was achieved at 18 h. The effect of concentration of tetrae...In this study, mesoporous silica/iron oxide nanocomposite(MCM-FeO) was synthesized via hydrothermal technique. The chemical synthesis of MCM-FeOnanocomposite was achieved at 18 h. The effect of concentration of tetraethylorthosilicate(TEOS) on nanocomposites properties was studied during synthesis process. For this purpose, 0.5, 1.5, 2.5, 3.5, and 4.5 ml tetraethylorthosilicate(TEOS) were selected, respectively. The textural properties and microstructure of the nanocomposites were characterized by X-ray diffraction(XRD), Fourier transform infrared spectroscopy(FTIR), field emission scanning electron microscopy(FESEM), Nadsorption-desorption, and vibrating sample magnetometer(VSM) analysis. Results show that the nanocomposite with tetraethylorthosilicate(TEOS)/cetyltrimethylammonium bromide(CTAB) ratio of 5 exhibits large surface areas(461.19 m~2·g). Furthermore, this nanocomposite shows superparamagnetic behavior under external magnetic field compared to other samples. Moreover, results of removal of metal ions indicate that adsorption of Ni(II), Cd(II), Cr(III),Zn(II), and Pb(II) ions on the surface of adsorbent(nanocomposite) increases with the increase in solution pH, contact time,and adsorbent dosage. Furthermore, the maximum removal rates of heavy metals ions reach 53.0 %, 79.0 %, 61.0 %,89.0 %, and 99.5 % at pH of 5, time of 50 min, and the weight of adsorbent of 0.16 with 2.5 ml TEOS, respectively.展开更多
A nanostructured ternary coating of Ti/（Ru ＋ Ti ＋ Ce）O2 was prepared by the conventional electrodeposition on the titanium substrate as the cathode with different numbers of coating layers. The main objective of t...A nanostructured ternary coating of Ti/（Ru ＋ Ti ＋ Ce）O2 was prepared by the conventional electrodeposition on the titanium substrate as the cathode with different numbers of coating layers. The main objective of this work was to study nanostructured coatings of ceramic materials. For this purpose, the amount of precursor materials in the electrolyte was a variable parameter. Furthermore, the salt of TiCl4/RuCl3·xH2 O/Ce（NO3）3·6 H2 O with different amounts, hydrogen peroxide, methanol, and distilled water were used as an aqueousunaqueous bath. In addition, the coated samples were put to heat at 300, 450, 650, and 850℃ in an electric furnace for1 h. The crystalline phase of the coating was characterized by X-ray diffraction（XRD）. The chemical composition and microstructure of the coating were studied using energydispersive spectroscopy（EDS） and scanning electron microscopy analysis（SEM）. Moreover, the electrochemical measurement of Ti/（Ru ＋ Ti ＋ Ce）O2 coatings was carried out. Results show that with the increase in the number of coating layers, the quality of morphology is improved.Then, the best quality of coatings is obtained at six layers on the titanium substrate with electrolyte including TiO2/RuO2/CeO2 with the molar ratio of 70：5：25 after heat treatment at 450 ℃ for 1 h. Besides,with the increase in Ce02 content from 5 wt% to 25 wt% and the number of coating layers, higher thickness of about（20.0±0.1） μm and minimum over potential for chlorine evolution were obtained.展开更多
The composite coatings of chitosan(CS)-bioglass^(■)(BG)-hydroxyapatite(HA)-halloysite nanotube(HNT)were investigated and produced via electrophoretic deposition(EPD)technique.The utilization of CS as a dispersing,ble...The composite coatings of chitosan(CS)-bioglass^(■)(BG)-hydroxyapatite(HA)-halloysite nanotube(HNT)were investigated and produced via electrophoretic deposition(EPD)technique.The utilization of CS as a dispersing,blending and charging agent for ceramic particles,including BG,HA and HNT,allowed the formation of CS-BG/HA/HNT composite,functionally graded composite(FGC)and bilayer film containing different layers.The results of scanning electron microscopy(SEM),energy-dispersive spectrometry(EDS),X-ray diffraction(XRD)and Fourier transform infrared spectroscopy(FTIR)illustrate the composite in the form of the optimum distribution of ceramic components in the CS matrix with thickness of 28μm on titanium(Ti)substrate.Electrochemical impedance spectroscopy(EIS)and potentiodynamic polarization tests indicate that the corrosion resistance of the coated sample increases in corrected simulated body fluid(C-SBF)at 37℃.Finally,the apatiteinducing ability of CS-BG-HA-HNT is proved by the formation of carbonated hydroxyapatite particles on composite coating in C-SBF.展开更多
基金financially supported by the Semnan University Foundation of Iran
文摘In this study, mesoporous silica/iron oxide nanocomposite(MCM-FeO) was synthesized via hydrothermal technique. The chemical synthesis of MCM-FeOnanocomposite was achieved at 18 h. The effect of concentration of tetraethylorthosilicate(TEOS) on nanocomposites properties was studied during synthesis process. For this purpose, 0.5, 1.5, 2.5, 3.5, and 4.5 ml tetraethylorthosilicate(TEOS) were selected, respectively. The textural properties and microstructure of the nanocomposites were characterized by X-ray diffraction(XRD), Fourier transform infrared spectroscopy(FTIR), field emission scanning electron microscopy(FESEM), Nadsorption-desorption, and vibrating sample magnetometer(VSM) analysis. Results show that the nanocomposite with tetraethylorthosilicate(TEOS)/cetyltrimethylammonium bromide(CTAB) ratio of 5 exhibits large surface areas(461.19 m~2·g). Furthermore, this nanocomposite shows superparamagnetic behavior under external magnetic field compared to other samples. Moreover, results of removal of metal ions indicate that adsorption of Ni(II), Cd(II), Cr(III),Zn(II), and Pb(II) ions on the surface of adsorbent(nanocomposite) increases with the increase in solution pH, contact time,and adsorbent dosage. Furthermore, the maximum removal rates of heavy metals ions reach 53.0 %, 79.0 %, 61.0 %,89.0 %, and 99.5 % at pH of 5, time of 50 min, and the weight of adsorbent of 0.16 with 2.5 ml TEOS, respectively.
基金financially supported by the Semnan University Foundation of Iran
文摘A nanostructured ternary coating of Ti/（Ru ＋ Ti ＋ Ce）O2 was prepared by the conventional electrodeposition on the titanium substrate as the cathode with different numbers of coating layers. The main objective of this work was to study nanostructured coatings of ceramic materials. For this purpose, the amount of precursor materials in the electrolyte was a variable parameter. Furthermore, the salt of TiCl4/RuCl3·xH2 O/Ce（NO3）3·6 H2 O with different amounts, hydrogen peroxide, methanol, and distilled water were used as an aqueousunaqueous bath. In addition, the coated samples were put to heat at 300, 450, 650, and 850℃ in an electric furnace for1 h. The crystalline phase of the coating was characterized by X-ray diffraction（XRD）. The chemical composition and microstructure of the coating were studied using energydispersive spectroscopy（EDS） and scanning electron microscopy analysis（SEM）. Moreover, the electrochemical measurement of Ti/（Ru ＋ Ti ＋ Ce）O2 coatings was carried out. Results show that with the increase in the number of coating layers, the quality of morphology is improved.Then, the best quality of coatings is obtained at six layers on the titanium substrate with electrolyte including TiO2/RuO2/CeO2 with the molar ratio of 70：5：25 after heat treatment at 450 ℃ for 1 h. Besides,with the increase in Ce02 content from 5 wt% to 25 wt% and the number of coating layers, higher thickness of about（20.0±0.1） μm and minimum over potential for chlorine evolution were obtained.
文摘The composite coatings of chitosan(CS)-bioglass^(■)(BG)-hydroxyapatite(HA)-halloysite nanotube(HNT)were investigated and produced via electrophoretic deposition(EPD)technique.The utilization of CS as a dispersing,blending and charging agent for ceramic particles,including BG,HA and HNT,allowed the formation of CS-BG/HA/HNT composite,functionally graded composite(FGC)and bilayer film containing different layers.The results of scanning electron microscopy(SEM),energy-dispersive spectrometry(EDS),X-ray diffraction(XRD)and Fourier transform infrared spectroscopy(FTIR)illustrate the composite in the form of the optimum distribution of ceramic components in the CS matrix with thickness of 28μm on titanium(Ti)substrate.Electrochemical impedance spectroscopy(EIS)and potentiodynamic polarization tests indicate that the corrosion resistance of the coated sample increases in corrected simulated body fluid(C-SBF)at 37℃.Finally,the apatiteinducing ability of CS-BG-HA-HNT is proved by the formation of carbonated hydroxyapatite particles on composite coating in C-SBF.
