Synthesis and optical characterization of Fe3O4 nanocomposites based on iron sand beach Glagah Kulon Progo combined with graphene oxide

Abstract

In this work, we have studied the effect of mass variation of graphene oxide (GO) on the lattice parameter, crystal structure, crystal size, surface morphology, and optical properties of Fe3O4/GO nanocomposite materials. The Fe3O4 was synthesized from the iron sand obtained from Glagah beach located in Kulon Progo, Yogyakarta, Indonesia by using the coprecipitation method. The resulted Fe3O4 was then doped with GO to become Fe3O4/GO nanocomposites by means of ultrasonication method. The composition of the nanocomposites was 5 mg Fe3O4 and 4 mass variations of GO, namely 4 mg, 8 mg, 12 mg, and 16 mg. Each composition was then dispersed in distilled water with a ratio of 1:3 for Fe3O4/GO to distilled water and ultrasonicated for 70 minutes at 35C. Based on XRD data, the mass variation of GO in Fe3O4/GO nanocomposites did not affect the lattice parameters and crystal structure, but did affect the crystal size. The lattice parameter value obtained in Fe3O4/GO is a=b=c=8,3967 A with a cubic crystal structure that has a crystal size of 167,9 nm, 169,1 nm, 158,3 nm, and 62,3 nm corresponding to the GO addition of 4 mg, 8 mg, 12 mg, and 16 mg, respectively. The typical SEM image of the Fe3O4/GO nanocomposite showed the surface morphology of GO in the form of sheets with a length of 6070,52 nm and a width of 2135,8 nm; and Fe3O4 in the form of grain with a grain size of 720 nm. Furthermore, the EDS characterization showed that the chemical composition of the main ingredients of sample 1 was 42,35% C, 39,9% O, and 6,06% Fe with 11,69% impurities, which indicates the success of the production of Fe3O4/GO nanocomposite. In addition, the UV-Vis spectra of the samples showed the change of the band gap of the nanocomposites with the change of GO composition, i.e. 1,94 eV and 2,9 eV for GO composition of 4 mg, 8 mg, respectively. Based on these XRD, SEM-EDS, and UV-Vis characterizations, the Fe3O4/GO nanocomposites have been successfully fabricated with the properties of crystal size and band gap are significantly affected by the addition of GO composition.