The paper presents a micro encapsulation method of α-Fe2O3 nanoparticles in PEG4000. A suspension of α-Fe2O3 nanoparticles and dissolved PEG is sprayed through a nozzle at atmospheric pressure. After rapid expansion, core-shell composite microparticles that don´t tend to agglomerate are obtained. Structure and morphology were investigated by electronic microscopy (TEM and SEM), X-ray diffraction (XRD), and spectral technique (UV-Vis and FTIR).
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