磁性γ-Fe_2O_3复合粒子的表面改性及其性能分析

Analysis on Surface Modification and Characterization of the Magnetic γ-Fe_2O_3 Nanoparticles

采用二乙三胺五乙酸（简称DTPA）对纳米γ-Fe2O3粒子的表面进行改性，制备出对金属离子具有良好整合效应的磁性γ-Fe2O3／DTPA纳米复合粒子，采用红外光谱（FTIR）、X射线衍射光谱（XRD）、透射电镜（TEM）、X射线光电子能谱（XPS）、比表面分析仪、振动样品磁强计（VSM）、原子吸收光谱（AAS）等对复合粒子的性能进行表征．结果表明：DTPA主要以化学吸附的方式包覆在γ-Fe2O3纳米粒子的表面，形成了纳米γ-Fe2O3／EDTA复合粒子；粒子复合以后，γ-Fe2O3粒子的分散性有所提高，复合粒子的粒径在20～30nm，比饱和磁化强度（σ）在65emufg左右，具有较强的磁性，并对多种金属离子（如Cu（Ⅱ）、Ni（Ⅱ）、Hg（Ⅱ）、Pb（Ⅱ）等）具有良好的螯合效应．

Magnetic composite particles of γ-Fe2O3/DTPA were got with DTPA as surface modification agent. The synthesized composite particles were characterized by fourier transform infrared spectra （ FF- IR）, X-ray photoelectron spectroscopy （XPS）, powder X -ray diffraction （XRD） ,transmission electronic microscopy （ TEM ）, vibrating - sample magnetometer （ VSM ）, and atomic absorption spectrum （AAS）, et al. The results showed that DTPA were chemically enwrapped on the surface of γ-Fe2O3 nanoparticles. The composite particles with 20 - 30 nm in diameter have a strong magnetism of 65 emu/g and a better dispersion. The composite particles could chelate with many mentalions such as Cu （Ⅱ）, Ni（Ⅱ）, Hg（Ⅱ）, and Pb（Ⅱ）.