Fe3O4基核壳纳米结构材料的制备及顺磁性研究OACSTPCD

Fe3O4@SiO2 core-shell nanostructured materials were prepared with Fe3O4 as magnetic core and SiO2 as shell.Surface hydrophilic modification of Fe3O4@SiO2 was carried out with triethoxysilane.The effects of hydrophilic modification on its paramagnetism and catalytic properties were studied.The results showed that Fe3O4 with cubic structure was the main crystal phase in the core-shell materials.The SiO2 at surface was amorphous,and the crystal structure of Fe3O4@SiO2 remained unchanged after surface hydrophilic modification.The Fe3O4@SiO2 material was irregular particles of 80-110 nm,in which the Fe3O4 was coated with SiO2.The saturated magnetization of the Fe3O4@SiO2 after hydrophilic treatment was reduced to 20.31 emu/g,indicative of superparamagnetism.This nanomaterial was applied to the wastewater containing Cd2+ for adsorption and degradation,where the removal rate was increased to 94.2%.The second-order kinetic model was more suitable for the adsorption of Cd2+ with Fe3O4@SiO2,and the correlation coefficient of the model was 0.994 3,showing good fitting.The results showed that the adsorption rate of Cd2+ by Fe3O4@SiO2 was greatly affected by chemisorption.