Effects of Adding Teos For Upr/Core-Shell Fe3O4@Sio2 Composites Nanoparticle from Iron Sand as Microwave Absorption Materials

This study aims for synthesized UPR/Core-Shell Fe3O4@SiO2 composites as microwave absorption materials. In this research nanoparticle, Fe3O4 was synthesized by using coprecipitation methods from the iron sand with NaOH solution. Core-Shell Fe3O4@SiO2 was synthesized by using StOber methods by using Tetraethylorthosilicate (TEOS) as precursor substances, where nanoparticle Fe3O4 as core and SiO2 the shell. The addition of TEOS was adding in the variation of volume and SEM study indicated that with an increase in TEOS content the particle of core-shell Fe3O4@SiO2 become bigger. Composites were synthesized with core-shell Fe3O4@SiO2 as the filler and UPR as the matrix. Then, composites were tested for electromagnetic microwave absorption using VNA (Vector Network Analyzer) at 8-12 GHz frequency. The result proved that UPR/Core-Shell Fe3O4@SiO2 composites were able to absorb electromagnetic waves at 9 GHz frequency with absorption large range up to - 15,8 dB.