Comparison of Microwave Adsorpsion of Core-Shell Fe3O4@SiO2 by Different Methods

Abstract

Abstract In this research, magnetite nanoparticles coated with sillica from rice husk ash (core-shell Fe3O4@SiO2) were synthesized by a modified stöber method through hydrolisis of silica using basic catalyst. Phase composition, morphology and microstructure were characterized using XRD, SEM, and TEM. The result shows that the sillica shell was successfully coated the core of nanoparticles magnetite. Core-shell Fe3O4@SiO2were synthesized using two method, first silica extraction and second through the silica gel. The application on microwave absorption are measured using VNA at the X-band frequency (8-12 GHz). Materials reach a reflection loss value of -34,29 dB at a frequency of 10,98 GHz for the first method (extraction of silica). For the second method (through silica gel), it exhibits two maximum absorptions with a reflection loss value under -20 dB, which are -23,05 dB at a frequency of 10,1 GHz and -25,03 dB at a frequency of 10,98 dB.