In this study, novel core-shell SiO<sub>2</sub>-coated iron nanoparticles (SiO<sub>2</sub>-nZVI) were synthesized using a one-step Stoeber method. The Malachite green degradation abilities of t...In this study, novel core-shell SiO<sub>2</sub>-coated iron nanoparticles (SiO<sub>2</sub>-nZVI) were synthesized using a one-step Stoeber method. The Malachite green degradation abilities of the nanoparticles were investigated. The effects of ethanol/distilled water volume ratio, presence and absence of PEG, tetraethyl orthosilicate (TEOS) dosage, and hydrolysis time used in the nanoparticles preparation process were investigated. The results indicated that the SiO<sub>2</sub>-coated iron nanoparticles had the highest reduction activity when the particles synthesized with ethanol/H<sub>2</sub>O ratio of 2:1, PEG of 0.15 ml, TEOS of 0.5 ml and the reaction time was 4 h. The SiO<sub>2</sub>-nZVI nanoparticles were characterized using Transmission Electron Microscopy (TEM), Energy Dispersive Spectrometry (EDS) and powder X-Ray Diffraction (XRD). The results showed that the average particles diameter of the SiO<sub>2</sub>-nZVI was 20 - 30 nm. The thickness of the outside SiO<sub>2</sub> film is consistent and approximately 10 nm. The results indicated that the nanoparticles coated completely with a transparent SiO<sub>2</sub>-film. Such nanoparticles could have wide applications in dye decolorization.展开更多
文摘In this study, novel core-shell SiO<sub>2</sub>-coated iron nanoparticles (SiO<sub>2</sub>-nZVI) were synthesized using a one-step Stoeber method. The Malachite green degradation abilities of the nanoparticles were investigated. The effects of ethanol/distilled water volume ratio, presence and absence of PEG, tetraethyl orthosilicate (TEOS) dosage, and hydrolysis time used in the nanoparticles preparation process were investigated. The results indicated that the SiO<sub>2</sub>-coated iron nanoparticles had the highest reduction activity when the particles synthesized with ethanol/H<sub>2</sub>O ratio of 2:1, PEG of 0.15 ml, TEOS of 0.5 ml and the reaction time was 4 h. The SiO<sub>2</sub>-nZVI nanoparticles were characterized using Transmission Electron Microscopy (TEM), Energy Dispersive Spectrometry (EDS) and powder X-Ray Diffraction (XRD). The results showed that the average particles diameter of the SiO<sub>2</sub>-nZVI was 20 - 30 nm. The thickness of the outside SiO<sub>2</sub> film is consistent and approximately 10 nm. The results indicated that the nanoparticles coated completely with a transparent SiO<sub>2</sub>-film. Such nanoparticles could have wide applications in dye decolorization.
